Word Study
ichthyosaurus
CIDE DICTIONARY
ichthyosaurus, n. [NL., fr. Gr. 'ichqy`s, -y`os, a fish + say^ros a lizard.].
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. [1913 Webster]
OXFORD DICTIONARY
ichthyosaurus, n. (also ichthyosaur) any extinct marine reptile of the order Ichthyosauria, with long head, tapering body, four flippers, and usu. a large tail.
Etymology
ICHTHYO- + Gk sauros lizard
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