/tahr"di grayd'/ , n.
1. Also called bear animalcule, water bear . any microscopic, chiefly herbivorous invertebrate of the phylum Tardigrada, living in water, on mosses, lichens, etc.
adj.
2. belonging or pertaining to the phylum Tardigrada.
3. slow in pace or movement.
[ 1615-25; tardigradus slow-paced. See TARDY, -GRADE ]