- ecu (n.)
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- old French silver coin, 1704, from French écu, "a shield," also the name of a coin, from Old French escu (12c.) "shield, coat of arms," also the name of a coin with three fleur-de-lys stamped on it as on the shield, formerly escut, from Latin scutum "shield" (see hide (n.1)). First issued by Louis IX (1226-1270); so called because the shield of France was imprinted on them.