[1] : The Collaborative International Dictionary of English v.0.48

ichthyosaurus \ich`thyosau"rus\, n.; pl. ichthyosauri. nl.,
   fr. gr. 'ichqy`s, -y`os, a fish + say^ros a lizard.
   paleon.
   an extinct genus of marine reptiles; -- so named from their
   short, biconcave vertebrae, resembling those of fishes.
   several species, varying in length from ten to thirty feet,
   are known from the liassic, o"olitic, and cretaceous
   formations.
   1913 webster
see also:
ichthyosauri 

[2] : WordNet (r) 2.0

ichthyosaurus
     n : ichthyosaurs of the jurassic
     also: ichthyosauri pl
see also:
ichthyosauri 

Ichthyosaurus >> I Words
Ichthyosaurus, definition of term: Ichthyosaurus
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