- Irish Legend. one of the great warrior kings of Ulster.
- a male given name.
- (in Irish legend) a warrior king of Ulster, who was supplanted by Conchobar
masc. proper name, from Gaelic Fearghus or Old Irish Fergus “man-ability,” first element cognate with Latin vir “man,” second from Old Irish gus “ability, excellence, strength, inclination,” from Celtic root *gustu- “choice,” from PIE root *geus- “to taste” (see gusto).