Ratite

Part of speech: noun

Pronunciation: /ˈɹætaɪt/

Definitions

1. A category of flightless avian species with a flattened breastbone, which distinguishes them from typical flying birds, and includes notable examples such as ostriches and emus
2. A classification of large, ground-dwelling birds that lack the anatomical features necessary for flight, recognized for their adaptability to land habitats and strong locomotion
3. A type of large, flightless bird characterized by a flat breastbone, lacking the ability to fly and found in various environments worldwide

Etymology: The name of this group of birds, which includes ostriches, emus, rheas, cassowaries and kiwis, rests on a comparison with boats. The Latin "ratis" meant "raft," and the suffix "-ite" was added to form a scientific term for the group. The link lies in the breastbone: most birds have a keel, a central ridge on the sternum that anchors the large flight muscles, while ratites lack this ridge. Their breastbone is flat, much like the hull of a raft, which has no keel to keep it steady through the water. The word is therefore a technical coinage built from a Latin noun and a suffix rather than an ancient term. Its meaning rests entirely on that anatomical contrast, so the bird is named for what it lacks rather than for anything it does. A raft and a flightless bird seem unrelated, but the shared absence of a keel is what linked them in the name.

Synonyms: flightless bird