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Irish surname

O'Monaghan: Irish Surname History & Coat of Arms

Ó Manacháin (also Ó Mancháin; spoken forms Ó Mionacháin, Ó Muineacháin) · 'descendant of Manachán' (diminutive of manach, a monk)

Woulfe (1923) gives O Monaghan, Monaghan and Monahan as forms of Ó Manacháin, 'descendant of Manachán' (diminutive of manach, a monk). The family descended from Manachán, a warrior mentioned by the Four Masters at the year 866, and were chiefs of Ui Briuin na Sionna in Co. Roscommon until 1249. Matheson's 1890 births index prints 'Monaghan (96)—Monahan (42)', with 140 for Ireland including spelling varieties.

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Coat of arms associated with the O'Monaghan surname
Irish formÓ Manacháin (also Ó Mancháin; spoken forms Ó Mionacháin, Ó Muineacháin)
Meaning'descendant of Manachán' (diminutive of manach, a monk)
CountiesRoscommon, Galway, Mayo, Dublin
Other spellings6

Origin of the O'Monaghan name

A Connacht family descended from Manachán, 'a famous warrior mentioned by the Four Masters at the year 866'. They were chiefs of Ui Briuin na Sionna, in the barony of Ballintober, Co. Roscommon, until 1249, when the O Beirnes ousted them. By the end of the 16th century the name was very scattered.[1]

  1. 866Manachán, ancestor of the family, mentioned by the Four Masters at this year.[1]
  2. 1249Ousted by the O Beirnes as chiefs of Ui Briuin na Sionna, Roscommon.[1]
  3. End of the 16th centuryThe name was very scattered.[1]
  4. 1890Monaghan (96), Monahan (42): 140 births including varieties; chiefly Galway, Mayo, Dublin, Fermanagh.[6][5]

Where in Ireland

Co. RoscommonÓ Manacháin were chiefs of Ui Briuin na Sionna, barony of Ballintober, until 1249.[1]
Co. GalwayFirst county named in 1890 for Monaghan births (including Monahan and other spellings).[6]
Co. MayoAmong the counties where Monaghan was principally found in 1890.[6]
Co. DublinAmong the counties where Monaghan was principally found in 1890.[6]
Co. FermanaghAmong the counties where Monaghan was principally found in 1890.[6]

Other spellings

Monaghan · Monahan · Manahan · O Managhane · Minahan · Menahan[1][2][6]

The O'Monaghan coat of arms

The design shown is a coat of arms associated with the O'Monaghan surname. In Irish and British heraldry a coat of arms is granted to one person and passes to their heirs; it does not belong to everyone who shares the surname. Many families still use the arms of their name as a symbol of their heritage.

O'Monaghan crest gifts

Clan Omonaghan Coat Of Arms - Irish Family Crest St Patrick's Day Classic CapVE77 Classic Cap - Omonaghan Coat Of Arms St Patrick's Day Classic Cap Irish Cap Omonaghan Coat Of Arms - Irish Family Crest St Patrick's Day Classic Cap£33.00Clan Omonaghan Coat Of Arms - Irish Family Crest Classic Cap YX69 Omonaghan Coat Of Arms Irish Cap Omonaghan Coat Of Arms - Irish Family Crest Classic Cap£26.00

O'Monaghan surname: questions

What does O'Monaghan mean?

Woulfe gives it as a form of Ó Manacháin, 'descendant of Manachán', Manachán being a diminutive of manach, a monk.[1]

Are O'Monaghan, Monaghan and Monahan the same name?

Woulfe lists O Monaghan, Monaghan, Monahan and Manahan among the anglicised forms of Ó Manacháin and its variant Ó Mancháin. Matheson's 1890 births index prints them in one entry, 'Monaghan (96)—Monahan (42)', with 140 for Ireland including spelling varieties.[1][2][6]

Where in Ireland is the O'Monaghan family from?

Ó Manacháin were a Connacht family, chiefs of Ui Briuin na Sionna in Ballintober barony, Co. Roscommon, until 1249. In 1890 births under Monaghan (including Monahan) were chiefly in Galway, Mayo, Dublin and Fermanagh.[1][6]

Why is Thornton listed as a form of the name?

Woulfe lists Thornton under Ó Muineacháin, which he calls an attenuated form of Ó Manacháin. He says it 'is popularly supposed to be connected with 'muineach,' thorny, and is consequently in some places 'translated' Thornton'.[4]

Sources

  1. Ó Manacháin — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/om/o-manachain.php
  2. Ó Mancháin — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/om/o-manchain.php
  3. Ó Mionacháin — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/om/o-mionachain.php
  4. Ó Muineacháin — Irish Names and Surnames (Rev. Patrick Woulfe, 1923), transcribed, LibraryIreland.com. libraryireland.com/names/om/o-muineachain.php
  5. Table Explanation (Birth Indexes of 1890) — Special Report on Surnames in Ireland (Robert E. Matheson, 1909), transcribed, LibraryIreland.com. libraryireland.com/matheson/report/births/table-explanation.php
  6. Monaghan — Birth Indexes of 1890 — Special Report on Surnames in Ireland (Robert E. Matheson, 1909), transcribed, LibraryIreland.com. libraryireland.com/matheson/report/births/monaghan.php

Note: Matheson's 1890 figures for a surname include its spelling varieties (Matheson, Table Explanation).