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Greaves [ebd]
only in 1 Sam. 17:6, a piece of defensive armour (q.v.) reaching from the foot to the knee; from French greve, "the shin." They were the Roman cothurni.
GREAVES [smith]
a piece of defensive armor which reached from the foot to the knee and thus protected the shin of the wearer. It was made of leather or brass.
Also see definition of "Greaves" in Word Study