| ORN | of or relating to ornithology |
|---|---|
| ORN | a zoologist who studies birds |
| ORN | the branch of zoology that studies birds |
| ORN | lightly built medium-sized dinosaur having extremely long limbs and necks with small heads and big brains and large eyes |
| ORN | lightly built medium-size theropods |
| ORN | bipedal herbivorous dinosaur |
| ORN | bipedal herbivorous dinosaur |
| ORN | widespread group including duck-billed dinosaurs and their early relatives (hadrosaurs |
| ORN | heavier-than-air craft that is propelled by the flapping of wings |
| ORN | platypus |
| ORN | type genus of the family Ornithorhynchidae |
| ORN | small densely furred aquatic monotreme of Australia and Tasmania having a broad bill and tail and webbed feet |