The Collaborative International Dictionary of English v.0.48:

Dicynodont \Di*cyn"o*dont\, n. [Gr. di- = di`s- twice + ? dog +
   'odoy`s, 'odo`ntos, tooth.] (Paleon.)
   One of a group of extinct reptiles having the jaws armed with
   a horny beak, as in turtles, and in the genus Dicynodon,
   supporting also a pair of powerful tusks. Their remains are
   found in triassic strata of South Africa and India.
   [1913 Webster]

WordNet (r) 3.0 (2006):

dicynodont
    n 1: a kind of therapsid