Merck Manual

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Terms Used to Describe the Respiratory System

Terms Used to Describe the Respiratory System

Medical Term

Description or Common Term

Alveoli

The sacs in the lungs where oxygen is transferred into the blood and carbon dioxide is transferred out of the blood

Bronchi

The largest branches from the trachea into the lungs

Bronchioli

The fine branches coming off of the bronchi

Epiglottis

Serves as a “trap door” on top of the larynx; keeps food out of the larynx and trachea while the animal is swallowing

Larynx

Voice box; located at the top of the windpipe (trachea)

Nasal

Pertaining to the nose

Nasopharynx

The upper part of the pharynx, at the far back of the nasal passages

Oral

Pertaining to the mouth

Oropharynx

The middle part of the pharynx, at the far back of the mouth

Paranasal sinuses

Often just called “sinuses”; the tissue-lined cavities in the skull just behind and above the eyes and along the sides of the nose

Pharynx

The passage between the back of the nose and the throat; it is separated (top to bottom) into the nasopharynx, oropharynx, and hypopharynx (throat)

Pleura

The sac that encloses the lung

Pulmonary

Pertaining to the lung

Rhino-

Pertaining to the nose

Trachea

Windpipe