Definition of: trachea

(trā′kē·ə) noun plural ·che·ae (-ki·ē)
1. Anat. The duct, composed of membrane and incomplete cartilaginous rings, by which air passes from the larynx to the bronchi and the lungs; the windpipe.
2. Zool. One of the passages by which air is conveyed from the exterior in air-breathing arthropods, as insects and arachnids.
3. Bot. A duct or vessel in plants, particularly one having spiral markings. [<Med. L <LL trachia <Gk. (artēria) tracheia a rough (artery), fem. of trachys rough]
—tra′che·al adjective