- a long, close-fitting garment worn by members of the clergy or others participating in church services.
- a lightweight, double-breasted ecclesiastical coat or jacket, worn under the Geneva gown.
- a member of the clergy.
- Christianity an ankle-length garment, usually black, worn by priests and choristers
1540s, “long loose gown,” from Middle French casaque “long coat” (16c.), probably ultimately from Turkish quzzak “nomad, adventurer,” (the source of Cossack), from their typical riding coat. Or perhaps from Arabic kazagand, from Persian kazhagand “padded coat,” from kazh “raw silk” + agand “stuffed.” Chiefly a soldier’s cloak 16c.-17c.; ecclesiastical use is from 1660s.