鱼龙
Ichthyosaur \Ich"thy*o*saur\, n. [Cf. F. ichthyosaure.] (Paleon.) One of the Ichthyosaura.
ichthyosaur n : any of several marine reptiles of the Mesozoic having a body like a porpoise with dorsal and tail fins and paddle-shaped limbs [also: {ichthyosauruses} (pl)]