late 14c. (mid-13c. in Anglo-Latin), "a kind of laced bodice, close-fitting body garment," from Old French corset (13c.) "bodice, tunic," diminutive of cors "body," from Latin corpus "body" (from PIE root *kwrep- "body, form, appearance").
Meaning "stiff supporting and constricting undergarment for the waist, worn chiefly by women to shape the figure," is from 1795. They fell from fashion around the time of World War I. Related: Corseted, corsetted (1829); corseting; corsetry.