In 2010 Keelin was #588 for boys (the most common spelling being Keelan) and #1120 for girls (the most common girls' spelling is Keelyn). Though it is often an anglicization of the girls' name Caoilfhionn, in modern American boys' usage it probably represents a 20th century coinage based on Keegan/Keenan/Kalen kinds of names. Keelan can also be an Irish surname, an anglicization of Ó Ceallacháin, which comes from a personal name meaning "strife." This surname is more often anglicized Callaghan, Callahan, or O'Callahan.See Also: Keelin, Caoilfhionn