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Webster 1913 Edition
Ichthyosaurus
‖
Ichˊthy-o-sau′rus
,Noun.
pl.
Ichthyosauri
(#)
. [NL., fr. Gr.
ἰχθύς
, -ύος
, a fish + σαῦροσ
a lizard.] (Paleon.)
An extinct genus of marine reptiles; – so named from their short, biconcave vertebræ, resembling those of fishes. Several species, varying in length from ten to thirty feet, are known from the Liassic, Oölitic, and Cretaceous formations.