A lot vs. Alot: 9 Grammatical Pitfalls
late 15c., "size of the body," from Old French cors "body" (see corpse); the meaning "body of a woman's dress, bodice" is from 1818 in fashion plates translated from French; 1843 in a clearly English context. Sense of "a bouquet worn on the bodice" is 1911, American English, apparently from French bouquet de corsage "bouquet of the bodice."
a small bouquet of flowers originally worn by women at the waist or bodice and later worn on the shoulder or wrist or pinned to a handbag. A florist constructs a corsage from the heads of flowers; he inserts wires through the calyx (the external leaves at the base of a flower), binds them with tape or ribbon, bends them into shape, adds leaves or foliage, and then adds a ribbon or other embellishment. Introduced during the 18th century, the wearing of a corsage, which was usually supplied by an escort, became a popular custom during the 20th century.