bronchus
Meaning of bronchus: A bronchus is one of the two large airways connecting the trachea to a lung, continuing the path air follows into the smaller airways.
Definition of bronchus
A bronchus is one of the two large air passages that branch from the trachea, the windpipe, with one bronchus leading into each lung. Its wall contains rings of cartilage that keep the passage open along with smooth muscle that can narrow or widen its diameter, and it is lined with cells that produce mucus and tiny hairlike cilia that sweep debris upward and out of the airway.
The plural form of bronchus is bronchi, and the right bronchus branches off the trachea at a more vertical angle and is somewhat wider and shorter than the left, a difference relevant to where an inhaled object is more likely to become lodged.
Within each lung, a bronchus continues to divide into progressively smaller branches, eventually forming the bronchioles and, further still, the tiny air sacs where oxygen and carbon dioxide are exchanged with the bloodstream.
Used in a sentence
Imaging identified narrowing of the left main bronchus.
Good to know
A bronchus is distinguished from a bronchiole mainly by size and the presence of cartilage in its wall, since bronchi contain cartilage while the smaller bronchioles do not.
Word origin
Where “bronchus” comes from
Formed from Greek bronchos, meaning windpipe.