Ó Mainchín
Ó MAINCHÍN—I—O Manihin, Manihin, Manihan, Manahan, Mannix; 'descendant of Mainchín' (diminutive of manach, a monk); a variant of Ó Mancháin, which see; the name of a family of Corca Laoighdhe, in South-West Cork; now scattered through Munster, especially Cork, Kerry and Limerick, and generally anglicised Mannix.
Alphabetical Index to Irish Surnames