a. A member of a fabulous or prehistoric race of people that lived in caves, dens, or holes.
b. A person considered to be reclusive, reactionary, out of date, or brutish.
2.
a. An anthropoid ape, such as a gorilla or chimpanzee.
b. An animal that lives underground, as an ant or a worm.
[From Latin Trglodytae, a people said to be cave dwellers, from Greek Trglodutai, alteration (influenced by trgl, hole, and -dutai, those who enter) of Trgodutai.]