The lingula of the lung is a tongue-shaped region of the left lung. It is also known by its Latin name, "lingula pulmonis sinistri", which means "little tongue of the left lung".

The lingula represents an analog for the middle lobe of the right lung, which is absent in the left lung due to the position of the heart on the left side of the thoracic cavity.

It is located on the anterior side of the left lung, inferior to the cardiac notch and superior to the oblique fissure.

The lingula is divided into two segments: the superior lingula and the inferior lingula. Each segment receives its air supply from its own tertiary bronchus — the superior lingular bronchus and inferior lingular bronchus, respectively — and works as a discrete unit within the lung.

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