A helmet, especially a light or ornamental one; in architecture or zoology, a helmet-shaped structure or crest.
From French casque, derived from Spanish casco, ultimately from Latin quassus (broken), referring to broken pieces of pottery that resembled helmets in shape.
Medieval knights wore casques that were so heavy they needed special neck supports, but the word comes from broken pottery — showing that armor design evolved from the simplest of observations!
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