What does alveolitis mean?
Alveolitis is a medical term for inflammation of the alveoli, the microscopic air sacs of the lungs. It is used in clinical and pathological descriptions of lung disease, especially when inflammation follows exposure to inhaled antigens, as in hypersensitivity pneumonitis, historically called extrinsic allergic alveolitis. The term can also describe acute or chronic inflammatory changes affecting lung tissue, depending on the underlying condition. Because the word specifies inflammation of the alveoli, it should not be used as a general synonym for every kind of pneumonia or lung injury. In reports and research, "alveolitis" often appears alongside terms describing severity, cause, or imaging findings. For general readers, its importance lies in showing that a diagnosis may concern not only infection but an immune-mediated inflammatory response. Its concise name and specialized medical history make it a useful example of how technical vocabulary can distinguish particular tissue processes from broader illnesses.
nounInflammation of the alveoli, especially the microscopic air sacs of the lungs where gas exchange occurs. The term is used in clinical and pathological descriptions of inflammatory lung disease.
- Inflammation of the lung alveoli, the tiny air sacs in which gas exchange occurs.
"The scan and biopsy indicated alveolitis associated with hypersensitivity pneumonitis."
"The report concluded that the patient's alveolitis resulted from prolonged exposure to mold."
"Researchers described acute alveolitis in laboratory animals exposed to purified fungal antigens."
The formal plural is rare; singular "alveolitis" is generally preferred in modern medical prose.
"The review compares several reported cases of alveolitides."
Alveolitis affects spaces so small that they can be seen only under a microscope, yet inflammation in them can make every breath difficult.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does alveolitis come from?
The word is a Latin-based medical formation combining alveolus with the suffix -itis, meaning inflammation. Latin alveolus means "small cavity" and is itself a diminutive of alveus, meaning "hollow" or "cavity." The suffix -itis comes from Greek and was widely used in modern medical terminology to name inflammatory conditions.
How alveolitis is actually used
Primarily formal medical and pathology terminology. It is usually treated as an uncountable noun in clinical prose, although a formal plural exists. The word names a particular inflammatory process rather than a single disease.
Easily confused with alveolitis
Alveoli are the tiny air sacs of the lungs, whereas alveolitis is the inflammation of those air sacs.