Kay

Kay has multiple distinct origins depending on the tradition in which it appears. As an English feminine name, it originated as a short form of names beginning with the letter K, particularly Katherine, which itself derives from the Greek Aikaterine, of uncertain but possibly pre-Greek origin. In Arthurian legend, Kay is the anglicized form of the Welsh Cai, likely derived from the Latin Caius, a Roman given name of uncertain meaning, borne by Sir Kay, the foster brother and seneschal of King Arthur. As a masculine name in Frisian, German, and Scandinavian traditions, it functions as an independent given name, sometimes considered a form of Gaius or related to Germanic roots, and connects to cognates such as Kai and Kaj.