The Collaborative International Dictionary of English v.0.48:

Theriodontia \The`ri*o*don"ti*a\, n. pl. [NL., fr. Gr. ? (dim.
   of ? a beast) + ?, ?, a tooth.] (Paleon.)
   An extinct order of reptiles found in the Permian and
   Triassic formations in South Africa. In some respects they
   resembled carnivorous mammals. Called also Theromorpha.
   [1913 Webster]

   Note: They had biconcave vertebrae, ambulatory limbs, and a
         well-developed pelvis and shoulder girdle. Some of the
         species had large maxillary teeth. The head somewhat
         resembled that of a turtle. The Dicynodont is one of
         the best-known examples. See Dicynodont.
         [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Theromorpha \The`ro*mor"pha\, n. pl. [NL.: Gr. qh`r beast +
   morfh` form.] (Paleon.)
   See Theriodonta.
   [1913 Webster]