We have created an index of the most common names of native, old Irish (pre-Norman) origin that were still popular first names for boys in 19th-century Ireland. Many of these names were later disguised by Latin and English "translations". This index is particularly useful for breaking down brick walls where an individual does not appear on record as expected, or if you are looking for an unusual or unique Irish name for your baby boy.
Does your Irish ancestor only appear on record once? Do other records seem to match, save for the first name? If you are flummoxed by how your ancestor could have so many aliases, read our unique index to those elusive old boys Irish names.
In the early 20th century, confidence in the official use of one's authentic Irish (Gaelic) personal name grew. So, in the Census of Ireland for example, a given name may have been recorded in English in 1901, but in Irish (or alternative spelling) in 1911.
To facilitate your Irish ancestry research, we will continue to update this index with as many known spelling variations as possible. To contribute to this resource, click HERE.
In this index most common Irish names, their correct English, Latin and Gaelic spelling variations are listed. This is followed by their meaning and origin, but before we begin please read through the index guide below.
Irish Gaelic [ga]
Anglicised [en] census link (Variations: nicknames, aliases, alternative spelling)
The original Irish / Gaelic is followed by how it was recorded in Latin (italics).
- Some letters in the English alphabet do not occur in Irish.
- Old Gaelic names were often batched together and disguised by one shared Anglicisation.
- To flag this, some Irish / Gaelic names (from entirely different roots) have been combined in the same box.
- How a Gaelic name was Latinized varied (and one individual could appear under any or all in the same parish register).
- Use of the Latin form of a Gaelic name was not exclusive to church records e.g. Thaddius.
- Some of these varied forms are common Irish American boys names.
The green indented text indexes all known variations in English (to include nicknames).
- Links to the 1901 Census have been included for the most popular spelling variant.
- [Origin] has been included as a hint to the county of origin, where the association is significant.
The key takeaway is, of course, that a Gaelic name could have been recorded under a variety of "translations" (one individual could have multiple aliases) depending on the transcriber.
To add to this index, please click HERE.
Traditional and ancient Irish boys names; their aliases, origin and meaning
To research a particular name (without having to scroll) use the FIND function on a desktop PC. The following keyboard shortcut will open a search/ find window:
Hold down the CTRL key [Mac = command].
Type in the name (or part of) and press RETURN.
No results? Re-try using a partial spelling of the name.
To submit a query or a suggestion, click here.
Some popular Irish Gaelic boys' names won't appear on this "Old Irish" list if they were introduced later by Normans e.g. Liam / Seán
Our index to Irish Christian names of Norman origin is coming soon. For notification, be sure to sign-up / join here.
Origin/ Meaning: In the province of Connacht, Aibhistín is a variant of Ághuistín, and Oistín is a Norse form of Augustine. In the Annals of Ulster in 874, Oistín was the son of Amhlaoibh, king of the Norsemen. Águistín is also the name of the renowned Bishop of Hippo, Doctor of the Church, and the Apostle of England, to which it owes its popularity in England. Prior to this, it was more commonly used as Austin, and this name has become more known and used in Ireland in comparatively recent times.
Origin/ Meaning: One of the variations of this name is Ailbhe. It was the name of the patron saint of the Diocese of Emly. St Ailbe died in 541, and his feast day is on September 12th. This name appears to have been applied to both girls and boys and it has been revived in recent times.
Hugo , Hugonis, Hugones
Origin/ Meaning: Aodh is an ancient Irish name with the meaning of fire. It was a favourite name among the O'Connors of Connacht and the O'Neills and O'Donnells of Ulster. It was one of the most frequent names for kings and chiefs among the Irish. The word signifies the Vesta of the pagan Irish and probably came from the religious worship of the Druids.
Origin/ Meaning: Aodhán is a diminutive of Aodh. The name was pretty common in the 8th and 9th centuries. In the Martyrology of Donegal, 23 saints with this name are mentioned. Another variation of this name is Aedan, and it is a common baptismal name.
[see also: Maodhóg below]
Origin/ Meaning: Three of the many variations of this name are Aengus, Angus and Aonghus, which has the meaning of great or excellent strength. These names are popular in Scotland. Its Celtic form is ‘Oino-gustu-s’, which comes from ‘oinos’, meaning one, and ‘gustus’, meaning choice. It is an ancient Irish name, and it was once widespread and frequently used among the MacDonnells, O'Dalys, O'Leynes. The Martyrology of Donegal mentions five saints with the same name. It is sometimes shortened to Naos.
[see also: Naos below]
Origin/ Meaning: One of the various forms of this name is Art with the meaning of noble, great, generous. Another source gives it the meaning of stone or bear. It is an ancient Irish personal name frequently used among the MacMurrough Kavanaghs, O'Connors and O'Molloys in Leinster, the O'Keeffes and O'Learys in Munster, the O'Haras and O'Rourkes in Connacht and the O'Neills in Ulster.
Beairtle, Bartlí / Partalán
Origin/ Meaning: Bartholomew, along with Betty, is the anglicised form of Mac Farlane (Mac Phárláin), the Dumbarton County sept, in Ulster and Scotland.
Origin/ Meaning: One of the known variations of this name is Brendan, and its meaning is brown raven. Saint Brendan of Clonfert is reputed to have sailed to America in the 6th century in the tradition of Saint Brendan's voyage to America (Thomas D'Arcy McGee, a history of the Irish settlers in North America, 1852).
Bernardus / Barnabus / Boeticus
Origin/ Meaning: It is derived from ‘bri’, meaning strength and ‘an’, meaning very great; hence giving it the meaning of a warrior of great strength, or it may be derived from ‘bran’, meaning a mountain torrent that implies powerful strength. It is a name made famous by king Brian Boru, the victor of Clontarf, and since then, it is a common name in most Irish families.
Carbery, Carbry, Carberry, Carbary
Origin/ Meaning: It is derived from ‘corb’, meaning chariot and ‘ri’ meaning king, signifying the ruler of the chariot. It is an old Irish name that was formerly common among the O’Farrells and O'Beirnes and is still used in a few families. In the Martyrology of Donegal, four saintly bishops of the name are mentioned. The Three Cairbres were influential founders of tribes in Ireland, according to Magaret Anne Cusack in An illustrated history of Ireland (1868).
Kevin, Cian, Kevan, Kevyn
Keane, Cain, Charles
Origin/ Meaning: Cian is an old Irish name, meaning ancient. Another source gives it the meaning of head. It was frequently used among the O'Haras and O'Garas of Connacht and the O'Carrolls of Ely who took it from their great ancestor, Cian, the son of Olioll Olum, King of Munster. It was also common among the O'Mahonys of south Munster, after their great ancestor Cian, the son in law of Brian Boru. He led the forces of Desmond at the battle of Clontarf. This name is still in use, but it is sometimes anglicised as Cain.
Charles, Cahal, Charlie, Charley, Sorley, Chas, Cha's, Charlo, Carrol, Carl, Karl
Origin/ Meaning: Cathal’s Celtic form is ‘Katu-Valo-s’, signifying the battle-mighty; it is an ancient and very common Irish name, especially among the O'Connors of Connacht, O'Farrells, O'Reillys, O'Rourkes and Maguires. It has the meaning of a great warrior and is derived from ‘cath’, meaning battle and ‘all’, meaning great. This name is featured in the legend of Cathal the King (Lady Wild, ancient legends, mystic charms and superstitions of Ireland, 1888). one of its famous variations is Chal and Cahill, which mean warlike.
[see also: Cearbhall below]
Carrol, Charles, Carl, Karl, Cearbhaill, Charles, Charlie, Charley, Sorley, Chas, Cha's, Charlo
Origin/ Meaning: Cearbhall was once a common Irish name, especially among the O'Dalys.
Kieran, Ciar, Kieron, Kerne, Cairn, Kierrin, Kyran, Kieren, Cairan, Kernan
Origin/ Meaning: Ciarán comes from ‘ciar’, signifying coal, black and zealous. In the Martyrology of Donegal, this name belongs to no fewer than fifteen Irish saints. The best known are St Kieran of Saighir, patron of the Diocese of Ossory and St Kieran the Abbot of Clonmacnoise and patron of that diocese. Their feasts are held on March 5th and September 9th, respectively. Ciarán is still a common Christian name in Cape Clear, and it is also used in parts of Connacht.
Origin/ Meaning: Cillian is a diminutive of Ceallach. It is the name of a celebrated missionary who was martyred at Wurtzburg in Germany, on July 8th, around the year 689.
Coleman, Colman, Callum
Origin/ Meaning: Colmán is a diminutive of Colm, meaning dove. It was one of the most common Irish names used by nearly one hundred Irish saints, of whom three are patrons of various Irish diocese, namely, Cloyne, Dromore and Kilmacduagh. Colm is also written as Colum, which is an old Irish name, signifying dove. It was made famous by St Columcille, Apostle of Scotland, whose name indicates the dove of the church.
Conor, Connor, Conchubhar, Con, Constantine, Conn, Connie, Conny
Origin/ Meaning: One of its variations is Conchobhar, an ancient and very common Irish name, meaning high will or desire. It is found in most Irish families, and it is still used today. It signifies the helping warrior and is derived from ‘cu’ or ‘con’, meaning above and ‘cobhair’, meaning aid.
Con, Constantine, Conn, Connie, Conny, Nialus
Origin/ Meaning: Conn is derived from ‘conn’, meaning wisdom. Some say it is derived from ‘cu’, with the meaning of a hound or swift-footed warrior. Its Celtic form is ‘Kondo-s’ signifying sense, reason and intelligence. It also means a freeman. It is an ancient Irish name, which was common among the O'Neills, O'Donnells and O'Rourkes. It was anglicised to Constantine in the 17th century, by the O'Neills.
Connell, Con, Conal, Coneily, Condy, Condaí, Conn, Connie, Conny, Condie, Condey.
Origin/ Meaning: It has the meaning of friendship, or it may be derived from ‘con’, meaning hound (as applied to a swift-footed warrior) and from ‘all’, meaning great or mighty. Its Celtic form is ‘Kuno-valo-s’, signifying the meaning high and mighty. It is an ancient and once common Irish personal name; it is still used among a few families. In the Martyrology of Donegal, eight saints of this name are mentioned.
Kenneth, Canice, Kenny, Coinneach
Origin/ Meaning: One of the variations of this name is Coinneach, which signifies the meaning of fair one. It was the name of the patron saint of Kilkenny.
Cormack, Charles, Cor, Corly, Corey, Corrie Neily, Neilus, Neil Cormick, Cormk.
Origin/ Meaning: Cormac signifies the son of the chariot. It is derived from ‘corb’, meaning chariot and ‘mac’, meaning son. Another source gives it the meaning of boy. it is an ancient Irish name that was very common among the MacCarthys, MacDermotts, MacDonoughs, Maguires, O'Clerys, O'Connors of Connacht' O'Donnells and O'farrells. Eight saints of the name are mentioned in the Martyrology of Donegal. It is a famous name in Irish history, for example, Cormac MacArt reigned for forty years in the 3rd century as king of Ireland (Alfred Webb, Cormac MacArt, A compendium of Irish biography, 1878).
Cooey, Quentin, Hughey, Quintin, Quinton, Conmhaighe
Origin/ Meaning: One of its known variations is Cooey, and its meaning is a dog of the plain.
Darra, Darragh, Dara, Darach, Darragh
Origin/ Meaning: Daire is an old Irish name.
Origin/ Meaning: Déaglán is a relatively common name in Co. Waterford. Also, it was the name of the patron of Ardmore. His feast is held on July 24th.
Demetrius / Dermicius
Dermot, Darby, Jeremiah, Jerome, Jerry, Derry, Diarmuid
Origin/ Meaning: Diarmaid is an old and widespread Irish name consisting of two parts: ‘di’, meaning without and ‘airmit’, meaning injunction. Therefore, the meaning freeman is given to it. Another source gives it the meaning of god of arms and that it is derived from ‘dia’, meaning god and ‘armaid’, meaning of arms. It was applied to a warrior as an epithet and was equivalent to one of Homer's heroes- Dios Krateros Diomedes or the god-like fighting Diomede. This name appears in the legend of the Pursuit of Diarmuid and Grainne (Ethna Carbery, in the Celtic past, 1904).
The name is still used, especially among the MacCarthys, MacDermotts, O'Briens and O'Connors. It is still found in every part of Ireland. Its anglicised version is Jeremiah. in the Martyrology of Donegal, eleven saints named Diarmaid are mentioned.
Denis, Donncha, Donny, Donnie, Dinnis, Dinny, Dinnie, Den, Don, Donie, Donal, Donaghy Donough, Donnchadh, Donnchad, Donnchadha, Dúnchad,
Origin/ Meaning: One of its variations is Donnchadh, which its Celtic form is ‘Donno-catu-s’, meaning brown or strong warrior. It is an ancient and widespread Irish name and is still found in every part of the country. It was the name of a saint, St Dunchadh, who was the Abbot of Iona and his feast day is on May the 25th.
This name is derived from the Clann Domhnaigh and is anglicised as Donogh and Denis in Ireland and as Duncan in Scotland.
Donovan Denis, Donncha, Donny, Donnie, Dinnis, Dinny, Dinnie, Den, Don, Donie, Donal
Danielus, Danieli, Donaldus, Donatius
Donald, Daniel, Donal, Dan, Danny, Donny, Donnie, Don, Donie, Donat, Domhnall, David (handwriting error)
Origin/ Meaning: One of the variations of this name is Domhnall which is derived from ‘domhan’ and ‘all’, meaning the world and mighty respectively. Another source gives it the meaning of world-ruler. Its Celtic form is ‘Dumno-valo-s’, meaning world mighty or ‘dubno-valo-s’, meaning mighty in the deep. It is one of the most ancient and famous Irish names, still in use in every part of the country, and it is generally anglicised as Daniel. It is also very popular in Scotland, where it is anglicised as Donald. Only one saint with this name is mentioned In the Irish Martyrologies, and his feast day was on April 26th.
Douglas, Doug, Douggie, Dougy, Dubhghlas
Origin/ Meaning: One of its common variations is Douglas. According to William Buchanan, in the early times, this name was written as MacDouglas, and the sept is descended from McDuff, Thanes of Fife, Scotland. The origin of the name comes from the black complexion and grey-green dress of the first owner of the name. it consists of ‘dubh’, meaning black, and ‘glas’, meaning green.
Edmond, Enda, Edward, Edmund, Ed, Eddie, Eddy, Ned, Neddy, Edwin, Edm., Edw. Éamonn
Origin/ Meaning: Éamonn is one of the variations of the name Éamon that means the blessed-protection. It was the name of a saintly king of England, who was martyred on November 20th, 870. Its Anglo-Saxon version is the name Edmund. It was introduced in Ireland by the Anglo-Normans, where it has become prevalent. It has almost completely absorbed the other common Anglo-Saxon name, Edward. The Irish version Éamonn generally stands for both names.
Éanna is an old Irish name made famous by St Enda, Abbot of Aran, whose feast is on March 21st.
Heberus Eberous Iberus
Ever, Heber, Ivor, Iobhar, Ivarr
Origin/ Meaning: Éibhear was a common name among the MacMahons and a few other families in Ulster. It was also common on Cape Clear Island. It is anglicised as Heber, and sometimes in the north of Ireland, as Ivor.
Íomhar comes from the Norse name, Ivarr. A name borrowed by the Irish from the Norsemen.
Eugenus Oenus Owenus
Eugene, Owen, Eoghan
Origin/ Meaning: Eoin’s Hebrew form is Jochanan signifying grace or gracious gift of Jehovah. It is common in all Christian countries. It has been used in Ireland from the early Christian time. It was one of the most frequent names among the Anglo-Norman settlers and is now one of Ireland’s most famous names.
Festus, Festy, Festie, Factnan
Origin/ Meaning: Fachtna means just and upright. It was the name of four Irish saints, one of whom was the patron of the Dioceses of Ross and Kilfenora. The name was formerly in use among the O'Kellys of Connacht, who anglicised the name to Festus.
Furgallum Fergallus Fernaldus Ternaldus
Farrell, Fergal, Ferdinand, Virgil, Fergie, Fergy / Ferdie, Fardy, Farrill, Ferrigal, Farrigal, Farage. Farrelle, Fregal
Origin/ Meaning: Feargal is derived from ‘fear’, meaning man, and ‘gal’, meaning valour. Hence it signifies a valiant warrior. It is the root of the Latin proper name Virgil and Irish surnames O’Farrell and O’Ferrall.
Frederick, Ferdinand, Fred, Freddie, Freddy Ed, Eddie, Eddy / Rick, Ricky
Origin/ Meaning: Feardorcha is composed of ‘fear’ and ‘dorcha’, meaning man and dark, respectively. Hence the meaning dark-complexioned man. It was a relatively common name in the 16th century and was in use down to comparatively recent times, but now it is probably obsolete.
Fardy, Fergie, Fergy, Gus, Gusty, Gustie, Gussy
Origin/ Meaning: Its most known variation is Fergus, meaning a strong warrior and is derived from ‘fear’ meaning man and ‘gus’ meaning strength.
Fidelmius Fedlimius, Fidelmidius Fedlimidius
Origin/ Meaning: It is an ancient Irish name, meaning the ever good. It was common among the Maguires, O'Connors, O'Donnells, O'Neills, and O'Reillys and was borne by 6 Irish saints, one of whom is patron of the Diocese of Kilmore. A variation of this name is Feidhlim, which signifies great goodness. It is derived from the Irish word ‘feile’, meaning hospitality.
Finbar, Barry, Fionnbharr
Origin/ Meaning: One of the variations of this name is Fionnbharr which is compounded of ‘fionn’ and ‘barr’, meaning fair and head, respectively. It was the name of several Irish saints, including the patron saint of the Diocese of Cork. Another variation is Bairrfhionn, shortened to Barra, which was the name of the patron saint of the Diocese of Cork.
Finnius, Finnianus Fionanus, Fingenus Finginus
Finn, Fineen, Florence, Florrie, Florry, Flor, Fionan, Finnan, Finnian, Finghín, Finneen, Finnin
Origin/ Meaning: It is an ancient Irish name with the meaning fair. It signifies as fair birth or fair offspring, and it was common among the MacCarthys, O'Sullivans, O'Mahonys, O'Driscolls and other families in West Munster who anglicised it as Florence. One of its forms is Finghin which was the name of a saint whose feast day is on February 5th.
Fintan / Fenton, Ferdinand
Origin/ Meaning: One of its various forms is Fintan. it is the diminutive of ‘fionn’, meaning fair. It was the name of up to 20 Irish saints, of whom one of the most celebrated was St Fintan of Clonenagh.
Flann, Flannán, Fitheal
Flan, Florence, Flannan, Florence, Florrie, Florry, Flor, Fithcheallach
Origin/ Meaning: Flann is an ancient and once common name meaning ruddy. Another source gives it the meaning of blood, signifying a red complexion. It was used among the MacEgans and O'Mulconrys up to recent times. In the Martyrology of Donegal, several saints with this name are mentioned.
Flannán is the diminutive of ‘flann’, meaning ruddy. it was the name of the patron saint of the Diocese of Killaloe, whose feast day is on December 18th.
Fitheal was used among the O'Mulconrys, who anglicised it to Florence.
Fiacrus Fiachus Fiachrius Festus /Fechinus
Festus, Feagh, Fiachra, Fiacre
Origin/ Meaning: One of its variations is Fiacha. It is derived from ‘fiacha’, meaning hunter and was a frequent name used for kings and chiefs from the earliest ages. Thus, it probably comes from the occupation or amusement of hunting which was so prevalent in earlier times.
Feichín is the diminutive of ‘fiach’ meaning raven; it was the name of five Irish saints, one of whom was Abbot of Fore and patron saint of West Connacht, where the name is now anglicised as Festus. St Feichin's day is January 20th.
Gill / Giles, Gillisa, Gillessa
Origin/ Meaning: Giolla means servant or disciple. The name Giolla is used as postfix, and therefore a multitude of baptismal names are created, such as Gillpatrick, Gillbride, Gillglass, etc. Giolla Íosa is an Irish name meaning servant of Jesus.
Giolla na Naomh
Origin/ Meaning: Giolla na Naomh is an Irish name, meaning servant of the saints.
Glasny, Glas, Glass
Origin/ Meaning: Glaisne was a formerly favourite name in several Ulster families, and it survived down to recent times.
Origin/ Meaning: Irial is an ancient Irish name formerly used among the O'Farrells, O'Kennedys and O'Loghlens.
Origin/ Meaning: Lachtna means green. It was the name of the great-grandfather of Brian Boru (king of Ireland); hence the name was used among the O'Briens.
Origin/ Meaning: Lúcán was the name of four Irish saints.
Lysagh, Lucius, Louis, Lewis
Origin/ Meaning: It is a derivative of Laoighis, i.e., belonging to Leix; it was used by the O'Mores and a few other families.
Loughlan, Loughlin, Lackey, Lacky, Lachy, Lanty, Larry, Luke, Luis, Laurence, Lawrence,
Origin/ Meaning: Lochlainn was borrowed from the Northmen. The Irish knew Lochlainn as the native home of the northern invaders, a name that is thought to signify Lakeland or Fiordland. This was quickly adopted by the Irish as a personal name and became very popular. Dr MacBain suggest that it was initially Maclochlainne, meaning son of Scandinavia, hence a Scandinavian. it is still in use, anglicised as Loughlin and Laughlin.
Origin/ Meaning: It is the diminutive of ‘lom’ meaning bare; it was the name of 4 Irish saints, one of whom was a disciple of St Patrick.
Origin/ Meaning: In pagan times this name was used as a "first" name. It is a diminutive of ‘lon’, meaning a blackbird, and it was the name of 8 Irish saints.
Origin/ Meaning: One of the variations of this name is Larry, and it is anglicised as Lawrence like St Lawrence O'Toole, who was the patron of the Diocese of Dublin. Rev Patrick Woulfe in "Irish names and surnames" says it is diminutive of ‘lorc’, meaning fierce.
Lorcan, Lewis, Louis, Aloysius, Louey
Origin/ Meaning: Lughaidh is an ancient Irish name borne by ten saints; it was a favourite name among the O'Clerys.
Origin/ Meaning: Maodhóg is a variant of Aodhán. The initial M represents the possessive pronoun ‘Mo’ meaning my; it is used as a prefix as a term of endearment to the name of saints.
Origin/ Meaning: Manus means great. Two of its known variation forms is Maghnus and Magnus. The Northmen adopted this name in honour of Charlemagne (Carolus Magnus), and it was introduced to Ireland by them. It became widespread among some Irish families, especially the O'Donnells of Tirconnell. Eight saints with this name are mentioned in the Roman Martyrology.
[Origin: Donegal/ Derry]
Origin/ Meaning: Maolbheannachta is an ancient Irish name, signifying one desirous of the blessing.
[Origin hint: Galway]
Origin/ Meaning: Mathghamhain is a well-known Irish name, signifying 'an ear'. It was borne by the brother of Brian Boru and shared among the O'Briens, O'Connors and O'Farrells. It is known as Matthew in its anglicised form in recent times.
Origin/ Meaning: Maolmórdha is derived from ‘mordha’ meaning proud and ‘maol’ (which was prefixed mainly to the names of ecclesiastics and signifies) meaning a 'bold or tonsured person who became the spiritual servant or devotee of some saint. It is an ancient Irish name signifying majestic chief and it was a favourite name among the O'Reillys, who anglicised it to Miles or Myles.
Miles, Myles, Mortimer Meyler, Milo, Miles, Myles Morty, Murthy
Origin/ Meaning: Maolmhuire is an Irish name, signifying “servant of the blessed virgin Mary”; it was a favourite name among the Mac Sweenys by whom it was anglicised Miles or Myles.
Maurice, Morgan, Mortimer Meyler, Milo, Miles, Myles Morty, Murthy
Origin/ Meaning: Maolsheachlainn is the name of a servant of St Secundinus. One of its variations is Maoileachlainn, which was used for a disciple of St Patrick. It was relatively common in the 10th and succeeding centuries, especially among the O'Melaghlens, O'Farrells, O'Kelys and O'Connors; it is still used today but generally known as Malachy.
Origin/ Meaning: Maolcholaim was used for a follower of Columba, and it was common in Scotland. It is an Irish name signifying “servant of St Columcille”, a royal name in Scotland, where it is still in use. However, it does not seem to have been a common name in Ireland.
[Origin: Northern Ireland]
Muirgheas | Muiris
Murgessius | Mauritius
Origin/ Meaning: Muirgheas is compounded of ‘muir’, meaning sea and ‘-ghus’, meaning choice; it was formerly a common Irish name, but now it is merged with the name Muiris.
Muiris is a Roman name for a man of Moorish lineage. It was borne by the captain of the Thebean legion who was martyred, along with his companions, by order of Maximian, in the 3rd century, in Switzerland. It was common among the Anglo-Norman settlers in Ireland.
Murtaugh, Mortimer Murty
Origin/ Meaning: Muircheartach is compounded of ‘muir’ and ‘ceart’, meaning sea and right, respectively; therefore, its meaning is given as sea-director, an expert at sea or able navigator. It is an ancient Irish name that was common among the O'Briens and O'Connors. It is still in use but is anglicised as Mortimer, with which it has no connection. It may signify a naval warrior or a chief who established his rights at sea. From Margaret Anne Cusack, in death of king Aengus, an illustrated history of Ireland, 1868, it was mentioned that "Muircheartach A.D. 504, was the first Christian king of Ireland".
Murrough, Morgan, Murty
Origin/ Meaning: Murchadh’s Celtic form is ‘Mori-catu-s’ which has the meaning sea-warrior. It is an ancient Irish name, formerly common in most Irish families, especially among the O'Briens, O'Flahertys. It is still in use but generally anglicised as Morgan. Another source states its meaning as sea protector. Brian Boru had a famous son, Murchadh, who destroyed all serpents to be found in Ireland (James Bonwick, Serpent faith, Irish Druids and Old Irish religions).
Murry, Murray, Mury, Mary,
Origin/ Meaning: Muireadhach may be derived from ‘muir’, meaning the sea and ‘eadhach’, meaning protector; it is a name equivalent to “admiral” and is anglicised as Maurice and Murray. It signifies the meaning seaman or lord and was formerly a widespread Irish name that was borne by two saints, one of whom is the patron saint of the Diocese of Killala.
Origin/ Meaning: Naomhán is a diminutive of ‘naomh’, meaning holy. it was the name of an Irish saint whose feast day was kept on September 13th.
Aonghus, Niece, Nicholas, Nace, Nence, Neece, Neese,
Origin/ Meaning: Naos is a pet form of Aonghus which was formerly common in Ulster and still extant in that province.
[Origin hint: Ulster]
Origin/ Meaning: Neasán is the name of five Irish saints, of whom the best known is St Nessan, the deacon of Mungret.
Niall, Néil, Niallán
Neil, Nicholas, Niallus, Niellus, Nellus, Neal, Nei, Nigel
Origin/ Meaning: Niall is an ancient Irish name meaning noble knight or champion. It is prevalent in Ulster among the O'Neills, O'Donnells, O'Dohertys and O'Boyles. It is still in use, but the genitive Néill is sometimes used instead. The name is probably most famously represented by Niall of the nine hostages in Irish history (Alfred Webb, a compendium of Irish biography).
Niallán is a diminutive of Niall.
Odranus / Otteranus
Oran, Otheran, Orn
Origin/ Meaning: Odhran is a diminutive of ‘odhar’, meaning pale-green, and it was the name of nine Irish saints, one of which is the patron saint of Waterford.
Origin/ Meaning: Oisín is a diminutive of ‘os’, meaning deer. It was the name of the Fenian poet, son of Fionn MacCumhail. Four Irish saints also bore this name.
Origin/ Meaning: Oscar’s meaning is bounding warrior. It is a common Norse name, meaning divine spear or spear of the Anses or gods. It is the same as the Anglo-Saxon Osgar (occurring in Domesday book), but ‘Oscar’ is also an Irish word, meaning champion or combatant. It was the name of the son of Oisín and grandson of Fionn MacCumhail, and it was also a name among the Maguires in the 14th century.
Raganaldus/ Reginaldus Randlphus
Reginald, Ronald, Randal, Raonall, Randall, Randolph, Ralph, Rághnall
Origin/ Meaning: Raghnall is a Teutonic name meaning Reignwald and mighty power. This Teutonic name reached us by two channels: first through the Norsemen when the Irish and Scottish Gaels largely borrowed it, especially the MacDonnells and by whom it was incorrectly anglicised, Randal; secondly, through the Anglo-Normans, among whom it was widespread.
Origin/ Meaning: Ronán is a diminutive of ‘ron’, meaning seal and sea-calf. It is an ancient Irish personal name that twelve saints bore. Another source gives it the meaning of man with a profusion of hair.
Origin/ Meaning: Ros is a rare name formerly used among the Mageoghegans, MacMahons, Maguires and O'Loghlens.
Ruairí, Ruaidhrí, Ránall
Rory, Roderick, Roger, Roddy, Randal, Ronald, Raghnall, Roddy, Ragnaill,
Origin/ Meaning: Ruaidhrí is a Norse name meaning fame-ruler. It is given the meaning of the valiant or red-haired king to it. It was introduced by the Norsemen and became very common in Irish families, now incorrectly anglicised as Roger. Ruaidhri O'Connor, king of Connaught, was the last monarch of Ireland before the Anglo-Norman invasion (Alice Stopford green, Irish nationality, 1911).
Justin, Justan, Justyn, Justen, Juston, Justinian
Origin/ Meaning: Searbhreathach is a compound of ‘soar’ and ‘breathach’, meaning noble judge. It was a common name among the MacCarthys, and the father of Cárthach bore it.
Sedanus, Sedonius, Sidonius
Sidney, Sydney, Sydny, Sidny
Origin/ Meaning: Séadna was an ancient Irish name that four saints bore.
Origin/ Meaning: Somhairle is a name of Norse origin meaning summer-sailor. it was especially common among the MacDonnells, who anglicised it as Sorley. Now it is known as Samuel and Charles.
Origin/ Meaning: Suibhne is an old Irish name meaning well-going. Seven Irish saints bore it.
Thaddeus, Thadius, Timotheus
Origin/ Meaning: Tadhg is an ancient and very common Irish name, meaning poet or philosopher. It is still found in every part of Ireland but is generally anglicised as Timothy. It was the name of St Tadhg, who was martyred at Wurtzburg. His feast day was observed on July 8th. It was also the name of a 16th-century Irish bard, Blind Tadhg O'Higgin (Eleanor Hull, the statue of Kilkenny(notes), a history of Ireland and her people).
Tordelvachus, Tobias,Terentius, Terricus
Turlough, Terence, Charles, Terry, Traolach, Tarla,Tarlach, Toirealach, Turlough, Tirlough
Origin/ Meaning: Toirdhealbhach is derived from ‘tor’ and ‘dealbhach’, meaning a tower and shape or form, respectively, signifying a man of tower-like stature. It is anglicised as Terence, Terrie and Terry.
Origin/ Meaning: Tiernan is a diminutive of Tighearna, signifying the meaning lord and lordly; it was a common name among the O'Rourkes. It was the name of St Tiernan, whose feast day was April 8th.
Tumelty, Timothy, Tobaltagh
Origin/ Meaning: One of the variations of Tumelty is Tomacltach. It is an old Irish name that was relatively common, especially among the O'Connors of Connacht. It is still in use but known more for the anglicised version of Timothy.
Origin/ Meaning: Tuathal’s Celtic form is ‘Touto-valo-s’, which means people-mighty. It is an ancient name and was once common in Ireland. It is still in use but is relatively scarce. Another source mentions it comes from ‘tuatha’, meaning territories. Its meaning is one possessed of large landed property.
Origin/ Meaning: Uaithne is an old Irish name found among the O'Mores and O'Loghlens by whom it was anglicised, Antony.
Origin/ Meaning: Ultán is the name of 18 Irish saints mentioned in the Martyrology of Donegal.
For writing this article, the following sources have been used:
Irish Names and Surnames by Revenant Patrick Woulfe
Irish Pedigrees by John O’Hart
The Irish Fireside by F. A. Fahy
Some Anglicised Surnames in Ireland by Padraig Mac Giolla-Domhnaigh.
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