(1) A tube-like portion of the breathing or “respiratory” tract that connects the “voice box” (larynx) with the bronchial parts of the lungs.
Each time we inhale (breathe in), air goes into our nose or mouth, then through the larynx, down the trachea, and into our lungs. When we exhale (breathe out), the air goes out the other way.
The esophagus, the tube that carries food from the mouth to the stomach, is just behind the trachea and the larynx. The openings of the esophagus and the larynx are very close together in the throat. When we swallow, a flap called the epiglottis moves down over the larynx to keep food out of the windpipe.
The trachea is also called the windpipe, weasand (sometimes written wesand or wezand) or wesil. “Cut his weasand with thy knife.” The Tempest, Shakespeare.
(2) Main airway that runs from the base of the throat down to the lungs. Divides into the two main bronchi (right and left) that supply each lung with air.