plural noun
Os·​te·​ich·​thy·​es | \ ˌästēˈikthēˌēz \

Definition of Osteichthyes

in some classifications
: a class or other category of fishes including the lungfishes, crossopterygians, teleosts, and especially formerly the arthrodires and ostracoderms and distinguished from other forms resembling fish by the presence of true bone in their skeleton — compare chondrichthyes

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History and Etymology for Osteichthyes

New Latin, from oste- + Greek ichthyes, plural of ichthys fish

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Cite this Entry

“Osteichthyes.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/Osteichthyes. Accessed 9 December 2019.

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