noun pl. tracheae -·cheae′ (-ē′) or tracheas -·cheas

1. in the respiratory tract of most land vertebrates, the tube extending from the larynx to the two bronchi; windpipe
2. in the respiratory system of insects and certain other invertebrates, any of the tubules branching throughout the body and conducting air from the exterior
3. Bot. vessel (sense )

Etymology: ME trache < ML trachea < LL trachia, windpipe < Gr tracheia (arteria), rough (windpipe) < trachys, rough, akin to thrassein, to confuse < IE base *dher-, dark residue, dirt > dregs