tabard (n.)

"sleeveless overgarment," c. 1300 (late 13c. as a surname), from Old French tabart "simple sleeveless overtunic," also "heavy over-mantel" (12c.), a word of unknown origin; Diez suggests Latin tapete "figured cloth." Compare Medieval Latin tabardum, early Spanish tabardo, Italian tabarro.

Originally a coarse, sleeveless upper garment worn by peasants, monks, and others who worked out-of-doors; later a knight's surcoat, richly adorned (mid-15c.).

The name of the tavern in "Canterbury Tales." Middle English Compendium points to another Middle English tabard meaning "small tank for holding ale or rainwater."