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protoavis

American  
[proh-toh-ey-vis] / ˌproʊ toʊˈeɪ vɪs /

noun

  1. a fossil bird of the genus Protoavis, from the Triassic Period, having a birdlike, partly toothless jaw structure, a tail and hind legs resembling those of the dinosaur, and the hollow bones and keellike breast that are characteristic of modern birds: the oldest known avian type, preceding the archaeopteryx by an estimated 75 million years.


Etymology

Origin of protoavis

< New Latin (1986), equivalent to Greek proto- proto- + Latin avis bird