The first name Katy is of French, Latin, Irish, Polish, Greek, Celtic/Gaelic origin. It is often a girl name. It has the following meaning(s):
French: Diminutive of Catherine: Pure, Clear. Form of the Latin Katharina, from the Greek Aikaterina
Latin: Diminutive of Catherine: Pure, Clear. Form of the Latin 'Katharina', from the Greek 'Aikaterina'. it Was Borne by a Number of Saints, Including St Catherine of Alexandria, a Th Century Martyr Who Suff
Irish: Diminutive of Katherine: Pure. Clear. from the Gaelic Form Caitlin