aventail

/ˈævənteɪl/

Etymology

From Middle English aventayle, from Old French esventail (“air-hole”), from esventer (Modern French éventer), from Latin ex (“out”) + ventus (“wind”). Related to ventail.

noun

  1. A curtain or flap of mail, fastened to a helmet, or to a coif (hood) of mail, covering the lower face, neck, and shoulders.“[…] the hood was increasingly replaced with a mail curtain (the camail or aventail) suspended from the outside of the bascinet, and the bascinet thus augmented gradually replaced the clumsy great helm as the principal defense […]”
  2. Synonym of ventail (“movable (solid plate) front to a helmet”).