Tardigrada \Tar`di*gra"da\, n. pl. [NL. See Tardigrade, a.]

1. (Zo["o]l.) A tribe of edentates comprising the sloths. They are noted for the slowness of their movements when on the ground. See Sloth, 3.

2. (Zo["o]l.) An order of minute aquatic arachnids; -- called also bear animalcules, sloth animalcules, and water bears.

Source: Webster's Revised Unabridged Dictionary (1913)