ichthyosaur

American  

[ik-thee-uh-sawr] / ˈɪk θi əˌsɔr /

noun

1. any fishlike marine reptile of the extinct order Ichthyosauria, ranging from 4 to 40 feet (1.2 to 12 meters) in length and having a round, tapering body, a large head, four paddlelike flippers, and a vertical caudal fin.

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ichthyosaur British  

/ ˈɪkθɪəˌsɔː /

noun

1. any extinct marine Mesozoic reptile of the order Ichthyosauria, which had a porpoise-like body with dorsal and tail fins and paddle-like limbs See also plesiosaur

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ichthyosaur Scientific  

/ ĭk′thē-ə-sôr′ /

1. Any of various extinct sea reptiles of the genus Ichthyosaurus and related genera, that had a medium-sized to large dolphin-like body with a dorsal fin, four flippers, and a large, crescent-shaped tail. The head had a long beak with sharp teeth, large eyes and earbones, and nostrils near the eyes on top of the skull. Ichthyosaurs were most common and diverse in the Triassic and Jurassic Periods and died out well before the end of the Cretaceous.

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Other Word Forms

• ichthyosaurian
  adjective
• ichthyosauroid
  adjective

Etymology

Origin of ichthyosaur

First recorded in 1820–30; see origin at ichthyosaurus

Example Sentences

See Examples For:

ichthyosaur

Moore had discovered an ichthyosaur in Dorset's cliffs and invited Sir David to be part of the excavation.

From BBC ● May 8, 2026

His first thoughts were that it might be another marine reptile like an ichthyosaur or plesiosaur.

From BBC ● Apr. 22, 2026

However, this marks the first new genus of Early Jurassic ichthyosaur described from the region in more than 100 years.

From Science Daily ● Feb. 24, 2026

The skull also appears to bear bite marks from a much larger predator -- likely another large ichthyosaur -- which may have caused its death.

From Science Daily ● Feb. 24, 2026

Buckland, I think, once indulged in the jeu d'esprit of supposing an ichthyosaur lecturing on the human skull.

From A journey in other worlds A romance of the future by John Jacob Astor