surcoat

noun

1. (historical)A loose sleeveless garment worn over a suit of armor, sometimes colored or embroidered with the wearer's coat of arms.

   “The ordered system of symbols which we know as heraldry came into being in the twelfth century to meet a military need. These symbols were emblazoned on shields, surcoats and fighting flags, and served as an invaluable means of identification when the features were obscured by the great helm.”

   “The Lord mayor and sheriff ride in their armour with surcoats of crimson.”

2. (historical)An overgarment worn over a woman's gown; a kind of short robe worn over the tunic at the close of the 11th century.

   “She wore a short surcoat of scarlet, cut low around the shoulders, sleeveless, reaching just below her hips, like the tabards worn by medieval heralds. Over it she wore a laced-edged cotta.”