Grap"nel (?), n. [OE. grapenel, dim. fr. F. grappin the grapple of a ship; of German origin. See Grape.] (Naut.) A small anchor, with four or five flukes or claws, used to hold boats or small vessels; hence, any instrument designed to grapple or hold; a grappling iron; a grab; -- written also grapline, and crapnel.