Source : Webster's Revised Unabridged Dictionary (1913)

Ophidia \O*phid"i*a\, n. pl. [NL., fr. Gr. ?, dim. of 'o`fis a
   snake.] (Zo["o]l.)
   The order of reptiles which includes the serpents.

   Note: The most important divisions are: the {Solenoglypha},
         having erectile perforated fangs, as the rattlesnake;
         the {Proteroglypha}, or elapine serpents, having
         permanently erect fang, as the cobra; the {Asinea}, or
         colubrine serpents, which are destitute of fangs; and
         the {Opoterodonta}, or {Epanodonta}, blindworms, in
         which the mouth is not dilatable.

Ophidion \O*phid"i*on\, n.; pl. {Ophidia}. [L., fr. Gr. ? little
   snake, fr. 'o`fis a serpent.] (Zo["o]l.)
   The typical genus of ophidioid fishes. [Written also
   {Ophidium}.] See Illust. under {Ophidioid}.

Source : WordNet®

Ophidia
     n : snakes [syn: {Serpentes}, {suborder Serpentes}, {suborder
         Ophidia}]