Kasey is a spelling variant of Casey, which comes from the Irish surname Ó Cathasaigh and means "vigilant" or "watchful"; the K-spelling was popular in the 1980s and 1990s for both sexes. NASCAR driver Kasey Kahne is a well-known male bearer. For boys in the United States Kasey ranked number 762 in 2000, peaked at number 634 in 2005 and stands at number 1162 in 2025.