the·co·dont 
(thēkə-dŏnt′)
(thēkə-dŏnt′)n.
Any of various extinct early archosaurs that existed in the Permian and Triassic Periods and had teeth set in sockets rather than attached directly to the jaw. The group Thecodontia in which they were once placed is no longer in scientific use.
[New Latin Thēcodontia, order name : Greek thēkē, chest, sheath; see dhē- in the Appendix of Indo-European roots + Greek -odōn, -odont-, -odont.]