Definition that contains jurassic period
- archaeopteryx extinct primitive toothed bird of the Jurassic period having a long feathered tail and hollow bones; usually considered the most primitive of all birds
- 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
- sinornis sparrow-sized fossil bird of the Jurassic period to the Cretaceous period having a keeled breastbone and vestigial tail; found in China; considered possibly the second most primitive of all birds
- archaeopteryx lithographica extinct primitive toothed bird of the Jurassic period having a long feathered tail and hollow bones; usually considered the most primitive of all birds
- pre-jurassic of or relating to or denoting the time before the Jurassic period