|Meaning||"descendant of Cadhla"|
|See also||Cawley, MacCawley, McCawley, Crowley|
O'Cawley is a surname in the English language. According to John O'Hart, a 19th-century Irish genealogist, the surname is an Anglicised form of the Irish Ó Cadhla. The Irish Ó Cadhla originated as a patronym, meaning "descendant of Cadhla". The masculine personal name Cadhla means "beautiful", "comely", "graceful". In the United States of America the surname is extremely uncommon, and did not rank in the 2000 United States Census.
- O'Hart, John (1892), Irish Pedigrees; or, the origin and stem of the Irish nation 2 (5 ed.), Dublin: J. Duffy and Co., Limited, pp. 305–306.
- Ó Cadhla, Library Ireland (www.libraryireland.com), retrieved 15 December 2010, this web page is a transcription of: Woulfe, Patrick (1923), Irish Names and Surnames.
- Genealogy Data: Frequently Occurring Surnames from Census 2000, United States Census Bureau (www.census.gov), retrieved 11 January 2011.