habergeon

noun3

1. •
   A hauberk, any coat of mail, less commonly even a coat of scale armour.

   • The defensive armour, or coat of mail of a knight, or man at arms, (also called a hauberk or habergeon,) was[…] — 1835
2. •
   (historical) A sleeveless or short-sleeved coat of mail armour (a shorter hauberk).

   • Their mightie strokes their haberieons dismayld, / And naked made each others manly spalles; […] — 1590
3. •
   (historical) The quilted undergarment worn under a hauberk.

   • His squire was already at his side, and helped with the coat of plates, the mail, the thick padded habergeon, and all the while Guillaume de Beaujeu was thinking, assessing, analysing, considering. — 2021