n. pl. tra·che·ae (-kē-ē′) or tra·che·as
1. Anatomy A thin-walled, cartilaginous tube descending from the larynx to the bronchi and carrying air to the lungs. Also called windpipe.
2. Zoology One of the internal respiratory tubes of insects and some other terrestrial arthropods, which are connected to the spiracles and are used for gas exchange.
3. Botany A tracheary element.
[Middle English trache, from Medieval Latin trāchēa, from Late Latin trāchīa, from Greek (artēriā) trākheia, rough (artery), trachea (as opposed to the smooth vessels that carry blood and not air), feminine of trākhus, rough.]
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