Actinopterygii

plural noun

Ac·​ti·​nop·​te·​ryg·​ii

¦ak-tə-ˌnäp-tə-ˈri-jē-ˌī

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

actinopterygious

¦ak-tə-ˌnäp-tə-ˈri-jē-əs

adjective

Word History

Etymology

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

First Known Use

1896, in the meaning defined above

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