As described in historical dictionaries

An Etymological Dictionary of Family and Christian Names (1857)

(origin: Gaelic.) From Fear, a man, and Syth, upright, honest, stiff.

Arthur, William (1857) An Etymological Dictionary of Family and Christian Names. New York: Sheldon, Blakeman. Public Domain.


Origin: Celtic

Region of origin: British Isles

Country of origin: Ireland

Religion of origin: Christian

Language of origin: Gaelic

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