Meaning: Its source is Caiside, an Irish Gaelic name meaning "Curly-headed."

Nicknames: Cass

Alternative Spellings: Kassidy

Source Forms: Caiside

Meaning: Its source is Caiside, a Gaelic name meaning "Curly-headed."

Languages: This girl's name is used in English.

Nicknames: Cass

Alternative Spellings: Casadee, Casidee, Casidy, Cassadi, Cassadie, Cassady, Cassiddy, Cassidee, Cassidi, Cassidie, Kasidy, Kassadi, Kassidee, Kassidi, Kassidie and Kassidy

Variant Forms: Cassadina, Casseday and Cassity

Popularity: The name Cassidy ranked 127th in popularity for females of all ages in a sample of 2000-2003 Social Security Administration statistics and 1817th in popularity for females of all ages in a sample of the 1990 US Census.

This name first made its appearance on state popularity lists of the 1990s, and has been trending upward in usage ever since.