The Collaborative International Dictionary of English v.0.48:

Gasteropod \Gas"ter*o*pod\, n. (Zool.)
   Same as Gastropod.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Gastropod \Gas"tro*pod\, n. (Zool.)
   One of the Gastropoda. [Written also gasteropod.]
   [1913 Webster]