Source : Webster's Revised Unabridged Dictionary (1913)

Notodontian \No`to*don"tian\, n. [Gr. ? the back + ?, ? a
   tooth.] (Zo["o]l.)
   Any one of several species of bombycid moths belonging to
   Notodonta, Nerice, and allied genera. The caterpillar of
   these moths has a hump, or spine, on its back.