New Latin, from archae- + Greek pteryx wing; akin to Greek pteron wing — more at feather
First Known Use: 1859
Oldest known fossil animal that is generally accepted as a bird (classified as genus Archaeopteryx). It flourished during the Late Jurassic period (159–144 million years ago). Fossil specimens indicate that archaeopteryx ranged in size from as small as a blue jay to as large as a chicken. Archaeopteryx shared anatomical characteristics with both birds (well-developed wings and birdlike skull) and theropod dinosaurs (well-developed teeth and a long tail).