Meaning & Origin
A surname from Middle English derived from several Old and Middle English words; also adopted by immigrants whose surnames began with a K.
Kay is a girl's and boy's baby name of Old English origin, functioning both as a standalone name and as a short form of names beginning with K — Katherine, Karen, Kathryn. It may also trace to the Old Welsh Cai, meaning 'rejoice,' and Sir Kay, one of King Arthur's original knights.
Kay was at its most popular in the 1930s and 1940s, when single-syllable feminine names felt both modern and smart. There is something effortlessly chic about Kay — it has the economy of a name that does not need to explain itself. Jazz singer Kay Starr and actress Kay Francis were defining faces of the era. Today it functions more often as a middle name, but its standalone appeal is quietly underrated.