archeopteryx archeopteryx /ˌɑːrkiːˈɒptərɪks/

noun

1. Extinct primitive toothed bird of the Jurassic period having a long feathered tail and hollow bones; usually considered the most primitive of all birds  ( archaeopteryx , Archaeopteryx lithographica , archeopteryx )
   extinct primitive toothed bird of the Jurassic period having a long feathered tail and hollow bones; usually considered the most primitive of all birds