also dew-claw, "rudimentary inner toe of the foot, especially the hind foot, of some dogs," 1570s, from claw, but the signification of the first element is obscure (compare dewlap).
Entries linking to dew claw
claw n.
"sharp, hooked, horny end of the limb of a mammal, bird, reptile, etc.," Old English clawu, earlier clea, "claw, talon, iron hook," from Proto-Germanic *klawo (source also of Old Frisian klawe "claw, hoe," Middle Dutch klouwe, Dutch klauw, Old High German klawa, German Klaue "claw").
Claw-foot in reference to carved furniture legs is from 1823; claw-and-ball attested from 1893. Claw-hammer, one having one end divided into two claws, is attested from 1769.
dewlap n.
mid-14c., dewelappe, "fold of skin that hangs from the throat of oxen and cows," from lappe "loose piece" (Old English læppa), but the first element is of unknown origin or meaning and probably has been altered by folk-etymology. Old English had fræt-læppa in this sense (Middle English fresh-lappe), and compare Danish doglæp. Later applied to the fleshy fold or wattle of a turkey and also to the human throat when flaccid with age (1580s).