What is the singular term for the main branch that comes off the trachea?

The main branch that comes off the trachea is referred to as a bronchus. The trachea bifurcates into two primary bronchi, which then lead into the lungs. A bronchus serves as a vital conduit for air to travel from the trachea into the lungs, where it further divides into smaller branches. Understanding the anatomy of the respiratory system is crucial, as it distinguishes the large airway (the trachea) from its initial divisions (the bronchi) that eventually lead to the smaller air passages in the lungs.

In contrast, bronchioles are further subdivisions of the bronchi and are much smaller in diameter. The trachea itself is the central airway, serving as the primary conduit for air before it splits into bronchi. The pleura comprises the membranes surrounding the lungs and does not relate to the branching structure of the airways. Hence, recognizing 'bronchus' as the singular term highlights its significance as the immediate passage that directs air from the trachea into the bronchial tree.