Theridiidae, the comb-footed spider

Theridiid is a noun literally meaning “a spider having a comb-like row of bristles on each hind foot.” The family name containing such spiders would naturally be called, Theridiidae. Widows are in this family of spiders sharing this common characteristic. A “comb foot” refers to the strong, curved bristles on the hind pair of legs which is used for flinging silk over its prey. Along with the tarsal claws (which you can see at the very end of the “foot”), you can easily see why they refer to these spiders as “comb-footed spiders.”