Meaning A varient of Katherine, an English name of Old Greek origin meaning 'pure, torture'. Origin of Cassy Greek Popular Middle Names AnnA Pronunciation 🔊 Listen Cassy KAES-iy Similar Names Catlyn Caitlan Katelyn Kathryn Grace Catelyn Cathleen Katelynn Caitlin-Rose Cadey Caelyn Year by Year Popularity of Cassy