|Region of origin||Ireland|
|Language(s) of origin||Irish|
|Related names||Ó Muircheartaigh|
The name Moriarty is an Anglicized version of the Irish name Ó Muircheartaigh which originated in County Kerry in Ireland. Ó Muircheartaigh can be translated to mean navigator or sea worthy, as the Irish word muir means sea (cognate to the Latin word mare for 'sea') and cheart means correct. Several people have the Irish name Moriarty, mostly as a surname.
Using documentary evidence, flavoured by legend, researchers have isolated historical data using books by O'Hart, McLysaght and O'Brien, the Four Masters, baptismals, parish records, and ancient land grants. Despite the loss of records caused by the fire in the Dublin Records Office in 1922 which was an irreparable disaster to Irish historians, sufficient evidence is still available to produce a thumbnail sketch of the Moriarty history.
Conclusions by these researchers show that the family name Moriarty was first found in county Kerry.
Spelling variations of the names were found in the archives researched, particularly when families attempted to translate the name from the Gaelic to the English. Although the name Moriarty occurred in many references, from time to time the surname was also officially recorded as Moriarty, O'Moriarty, Murtagh, Murtag, McMoriarty, O'Murtagh, and these changes in spelling frequently occurred, even between father and son. Preferences for different spelling variations usually arose from a division of the family, or for religious reasons, or sometimes patriotic reasons. Church officials and scribes spelt the name as it sounded, sometimes several different ways in the lifetime of the same person. The abbreviations of Mc in front of a name, meaning 'son of' is popular in Irish names, although this is no guarantee that the name is Irish. Many Scottish names also prefer Mc instead of Mac. Officially in both countries, the abbreviation is Mac. In Ireland, frequently O' is also used instead of Mc but meaning the same, that is, 'son of'.
In North America some of the first migrants which could be considered kinsmen of the sept Moriarty of that same family were Daniel, Ellen, Eugene, Margaret, Michael, Thomas Moriarty all settled in Boston in 1849; James, John, Martin, Maurice, and Michael Moriarty all arrived in Philadelphia between 1840 and 1860.
List of notable people with this surname
- Bill Moriarty, American baseball player active in 1909
- Brendan Moriarty, ophthalmic surgeon mostly known for introducing intraocular telescope surgery for macular degeneration
- Brian Moriarty, computer game author mostly known for Trinity and Loom
- Cathy Moriarty, American actress nominated for a Best Supporting Actress Academy Award for her role in Raging Bull
- Cecil Moriarty, Irish rugby international
- Clare Moriarty, British civil servant
- Colin Moriarty, Kindafunny Co-founder
- Colm Moriarty, Irish professional golfer
- Dan Moriarty, several people
- David Moriarty, Irish Roman Catholic bishop and pulpit orator
- David H. Moriarty (1911–1989), American sound engineer
- Dean Moriarty, character in Jack Kerouac's novel On The Road.
- Erin Moriarty, American actress
- Erin F. Moriarty, American television news reporter
- Fiach Moriarty, Irish singer, songwriter
- Gene Moriarty, Major League Baseball outfielder
- George Moriarty, American baseball player and umpire
- George Andrews Moriarty, Jr, American genealogist
- Jack Moriarty, Australian rules footballer
- James Moriarty, several people
- Jason Moriarty, American documentary film director
- Jeremiah J. Moriarty (1914–1995), New York politician and judge
- Jerry Moriarty, American artist
- Joan Denise Moriarty (1912?–1992), Irish dancer, teacher, choreographer, founder of professional ballet in Ireland
- John Moriarty, several people
- Judith Moriarty, American politician
- Kieran Moriarty CBE, British physician
- Laura Moriarty, American author from Hawaii
- Laura Moriarty, American poet and novelist from Minnesota and now residing in Northern California
- Liane Moriarty, Australian author
- Michael Moriarty, several people
- Patrick Moriarty, American politician, former mayor of Ashland, Kentucky
- Paul Moriarty, American politician
- Paul Moriarty, British actor
- Paul Moriarty, Welsh former international rugby union and rugby league player
- P. H. Moriarty (born 1939), British actor
- Professor Moriarty, fictional character, archenemy of Sherlock Holmes
- Richard Moriarty, Welsh former international rugby union captain
- Robert Moriarty, American Marine F-4B fighter pilot
- William Moriarty, a leader of the Communist Party of Canada who sided with the Right Opposition
- Moriarty (disambiguation)
- Jay Moriarity, American surfer
- Mícheál Ó Muircheartaigh, Irish Gaelic Games commentator
- Drew McWeeny, film critic who writes under the pseudonym "Moriarty"
- Moriarty family pedigree at Library Ireland