noun ich·thyo·sau·rus \-rəs\

Definition of ichthyosaurus

  1. 1 capitalized :  the type genus of Ichthyosauridae comprising highly variable Jurassic ichthyosaurs and originally including most of the later ichthyosaurs most of which are now placed in other genera

  2. 2 plural -es :  any reptile of the genus Ichthyosaurus

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Origin and Etymology of ichthyosaurus

New Latin, from ichthy- + -saurus

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to criticize severely

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