Wordnet 3.0
NOUN (1)
1. 
 a class of mollusks typically having a one-piece coiled shell and flattened muscular foot with a head bearing stalked eyes; 
[syn: gastropod, univalve]
The Collaborative International Dictionary of English v.0.48:
Gastropod \Gas"tro*pod\, n. (Zool.)
   One of the Gastropoda. [Written also gasteropod.]
   [1913 Webster]
WordNet (r) 3.0 (2006):
gastropod
    n 1: a class of mollusks typically having a one-piece coiled
         shell and flattened muscular foot with a head bearing
         stalked eyes [syn: gastropod, univalve]