Pronunciation: ' kä-t ə -l ō - ˌ so ̇ r, k ə - ' ti-l ə -
Function: noun
Etymology: ultimately from Greek kotyl ē + sauros lizard
Date: 1895
: any of an order (Cotylosauria) of extinct primitive reptiles of the Carboniferous to Triassic with short legs and massive bodies that were prob. the earliest truly terrestrial vertebrate animals