osteichthyan

noun

os·​te·​ich·​thy·​an ˌä-stē-ˈik-thē-ən 

variants or less commonly osteichthian

plural osteichthyans also osteichthians

: a fish of the class Osteichthyes : a bony fish

Extant jawed vertebrates, or gnathostomes, fall into two major monophyletic groups, namely chondrichthyans (cartilaginous fishes) and osteichthyans (bony fishes and tetrapods).

—Hector Botella et al., Nature, 2 Aug. 2007

osteichthyan adjective

or less commonly osteichthian

osteichthyan fishes

Word History

First Known Use

1967, in the meaning defined above

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