a broad piece of defensive armor, carried on the arm, -- formerly in general use in war, for the protection of the body. see buckler.-anything which protects or defends; defense; shelter; protection.-figuratively, one who protects or defends.-in lichens, a hardened cup or disk surrounded by a rim and containing the fructification, or asci.-the escutcheon or field on which are placed the bearings in coats of arms.  cf. lozenge. see illust. of escutcheon.-a framework used to protect workmen in making an adit under ground, and capable of being pushed along as excavation progresses.-a spot resembling, or having the form of, a shield.-a coin, the old french crown, or ecu, having on one side the figure of a shield.-to cover with, or as with, a shield; to cover from danger; to defend; to protect from assault or injury.-to ward off; to keep off or out.-to avert, as a misfortune; hence, as a supplicatory exclamation, forbid!