D defs.my
Entry 2 senses Webster, 1913

Chapeau

· Cha·peau · IPA /ʃæˈpoʊ/
01 n. A hat or covering for the head.
pl. Chapeux ((#))
  1. 1.
    A hat or covering for the head.
  2. 2.
    A cap of maintenance. See Maintenance.(Her.) See: Maintenance
Phrases & compounds
‖Chapeau bras — a hat so made that it can be compressed and carried under the arm without injury. Such hats were particularly worn on dress occasions by gentlemen in the 18th century. A chapeau bras is now worn in the United States army by general and staff officers.