The name Cassidy comes from the Irish surname Ó Caiside meaning "descendant of Caiside". The name Caiside itself means "curly-headed" in Gaelic.
Famous bearers
Bearers include Cassidy O'Reilly (born 1976), an American male wrestler;
Cassidy Rae (born 1976), an American actress;
Cassidy Freeman (born 1982), an American actress.