plural noun

: an order of Mesozoic marine reptiles most abundant in the Lias having an ichthyoid body, elongated snout, short neck, dorsal and caudal fins, limbs modified into paddles by the flattening of the bones, multiplication of the phalanges and addition of from one to four digits, eyes very large and protected by a ring of bony sclerotic plates, and numerous conical teeth set in grooves and adapted for catching fish
ichthyosaurian adjective or noun

Word History


New Latin, from ichthy- + -sauria

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Dictionary Entries Near Ichthyosauria

Cite this Entry

“Ichthyosauria.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Ichthyosauria. Accessed 29 May. 2024.

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