"do you understand?" 1940s slang, from Italian capisci? "do you understand?" from capire "to understand," from Latin capere "seize, grasp, take" (from PIE root *kap- "to grasp"). Also spelled coppish, kabish, capeesh, etc.
capeesh
Capella
caper
Capetian
capias
capiche
capillarity
capillary
capital
capital letter
capitalise