Archaeornithes

plural noun

Ar·​chae·​or·​ni·​thes

-ˈȯrnəˌthēz,

-ˌȯrˈnī(ˌ)thēz

: a subclass of Aves comprising the earliest and most primitive of fossil birds, retaining distinctive reptilian characters, and including the two genera Archaeornis and Archaeopteryx

Word History

Etymology

New Latin, from archae- + -ornithes

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