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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Origin and Etymology of actinopterygii
New Latin, from actin- + -pterygii (from Greek pteryg-, pteryx wing); akin to Greek pteron feather, wing — more at feather
First Known Use: 1896
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