A crab’s claw, or a lobster’s claw, is the pincer at the end of those creatures’ front limbs, which they use for defense. It’s a period charge, found in the arms of Nielsen, c.1490 [Raneke 395]. They’re frequently found in pairs, as in the arms of Stainhauser or Steinhauser, mid-16th C. [NW 32], and of Tregarthicke, 1610 [Guillim1 171].
The crab’s claw has its severed end to base by default; the illustration shows a crab’s claw bendwise. See also leg.
The Order of the Crab Claw, of the Barony of Lochmere, bears: A pair of crab claws azure maintaining between them a sword gules.