tabard

noun

1. a loose outer garment, sleeveless or with short sleeves, especially one worn by a knight over his armor and usually emblazoned with his arms.
2. an official garment of a herald, emblazoned with the arms of his master.
3. a coarse, heavy, short coat, with or without sleeves, formerly worn outdoors.

noun

1. a sleeveless or short-sleeved jacket, esp one worn by a herald, bearing a coat of arms, or by a knight over his armour

n.mid-13c., from early Spanish tabardo and Old French tabart (12c.), of unknown origin. Originally a coarse, sleeveless upper garment worn by peasants, later a knight’s surcoat (hence the name of the tavern in “Canterbury Tales”).