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n. A helmet, especially an ornate visorless headpiece of the 16th century.

n. Zoology A helmetlike structure or protuberance.

n. A visorless helmet.

n. A hard structure on the head of some birds, such as the hornbill or cassowary.

n. A piece of defensive or ornamental armor (with or without a vizor) for the head and neck; a helmet.

n. A helmet of any kind.

n. In zoology, some process or formation on the head resembling a helmet; a galea.

n. (15-16th century) any armor for the head; usually ornate without a visor

"On top of the head is a "casque" - a helmet-like growth of tough skin."

helmet   

casquet    casquetel   

helmet   

morion    cuirass    breastplate    headpiece    helm    hauberk    gagne    halberd    battle-axe    targe