corset

Concise Oxford English Dictionary © 2008 Oxford University Press:
corset/ˈkɔːsɪt/

▶noun a woman's tightly fitting undergarment extending from below the chest to the hips, worn to shape the figure.

■ a similar garment worn to support a weak or injured back.

■ historical a tightly fitting laced or stiffened outer bodice or dress.

– derivatives
corseted adjective,
corsetry noun.

– origin ME: from OFr., dimin. of cors ‘body’, from L. corpus.