Kelleher

Kelleher is an Irish surname. It is an Anglicized form of Gaelic surnames Ó Céileacháin or Ó Ceallaigh, both associated with descendants of a personal name. The precise origin varies by family line, with different regions adopting the name in the course of Irish history.

Etymology: Ó Céileacháin means "descendant of Céileacháin" and Ó Ceallaigh means "descendant of Ceallach." The name’s appearance in medieval Irish records and local pedigrees reflects its roots in Gaelic society and the common practice of forming surnames from ancestral names.

Distribution: The name is most common in Ireland, particularly in Munster (for example, Cork and Kerry), and it spread through the Irish diaspora to the United States, Canada, Australia, and Britain. Today many people with the surname Kelleher can be found in these countries and in Irish communities worldwide.

Variants and notes: Spelling variations arise from Anglicization and transliteration over the centuries. Records may show Kelleher and Kellaher, among other nearby spellings, reflecting regional and historical differences in pronunciation and orthography. The surname is associated with multiple Gaelic origins, leading to a degree of unrelated family lines sharing the same Anglicized form.