The Collaborative International Dictionary of English v.0.48:

Lepidosauria \Lep`i*do*sau"ri*a\ (-d[-o]*s[add]"r[i^]*[.a]), n.
   pl. [NL., fr. Gr. lepi`s -i`dos, a scale + say^ros a lizard.]
   (Zool.)
   A division of reptiles, including the serpents and lizards;
   the Plagiotremata.
   [1913 Webster]

WordNet (r) 3.0 (2006):

Lepidosauria
    n 1: diapsid reptiles: lizards; snakes; tuataras [syn:
         Lepidosauria, subclass Lepidosauria]