1. grapnel - Noun
2. grapnel - Verb
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.
Source: Webster's dictionaryGrapnel anchor A traditional design, the grapnel is merely a shank with four or more tines. Source: Internet
In the United States, SAA International Ltd manufacture a 150 ft·lb crossbow-launched version of the U.S. Army type classified Launched Grapnel Hook (LGH), among other mine countermeasure solutions designed for the middle-eastern theatre. Source: Internet
Special "grapnel tanks" towed hooks to pull away the German barbed wire. Source: Internet