plural noun
Ac·​ti·​nop·​te·​ryg·​ii | \ ¦ak-tə-ˌnäp-tə-ˈri-jē-ˌī\

Definition of Actinopterygii

in many classifications
: a subclass or other division of Teleostomi comprising fishes having the projecting part of the paired fins supported only by dermal rays and being coextensive with the Teleostomi excluding the Choanichthyes

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Other Words from Actinopterygii

actinopterygious \ ¦ak-​tə-​ˌnäp-​tə-​ˈri-​jē-​əs \ adjective

First Known Use of Actinopterygii

1896, in the meaning defined above

History and Etymology for Actinopterygii

New Latin, from actin- + -pterygii (from Greek pteryg-, pteryx wing); akin to Greek pteron feather, wing

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The first known use of Actinopterygii was in 1896

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