— cotylosaurian , adj.
/kot"l euh sawr'/ , n.
any member of the extinct order Cotylosauria, comprising heavy-bodied, splay-limbed, plant-eating reptiles that arose during the Carboniferous Period and that are considered to include the ancestors of all other reptiles.
[ 1900-05; Cotylosauria, equiv. to cotyl ( lus ) a hollow space in the bones forming the distinctive articulation of skull and vertebrae, which orig. defined the order (masc. n. kotýle socket, cup, anything hollow) + -o- -O- + -sauria; see -SAUR, -IA ]