Meaning A boy's name of Latin origin, it means "vain." Origin of Cassius Latin +-100%Zoom level changed to 1 Popular Middle Names James, Jett, John, Kenrick, Lamont, Lawrence, Leon, Lucian, Maximus, OShea Pronunciation 🔊 Listen Cassius CASS-ee-us Similar Names Adie Aabid Alex Bautista Cullen Colm Cathal Colin Connor Cian Year by Year Popularity of Cassius