The first name Kay is female and male.
The origin of the name Kay is not clear. It is presumably a Frisian short form of Gerard or Nikolaus, but as well of the Latin name Cajetanus and is of Celtic origin. It is a name for boys and seldom for girls (from Latin Cajetana or Katharina).
Kay means “warrior” (from Frisian “kempe”), “victory of the people” (from Nikolaus), “brave spearman” (from Gerard), “from the town Gaeta” (from Cajetanus), in Celtic “spear bearer/thrower”. For girls, Kay means “from the town Gaeta” (from Cajetana) or “pure” (from Katharina).