Definition of "ventail"
noun:
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A piece of armour used to protect the neck.
from Wiktionary, Creative Commons Attribution/Share-Alike License -
The movable front part of a helmet, originally including the visor but later specifically the separate lower section.
from Wiktionary, Creative Commons Attribution/Share-Alike License -
That part of a mediaeval helmet which is intended for the admission of air.
from Wiktionary, Creative Commons Attribution/Share-Alike License
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