Definition of pneumonitis
: acute or chronic inflammation of the lungs that is characterized especially by cough, shortness of breath, fatigue, and fever, and may result in the development of fibrotic scar tissue when chronic or untreated
Note: While pneumonitis and pneumonia are often used synonymously, pneumonitis is typically used when the cause is a noninfectious agent (such as a chemical or radiation).
The fungus caused an outbreak of hypersensitivity pneumonitis, an inflammation of the lungs triggered by an allergic reaction.— Faye RiceTest Your Vocabulary
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Merriam-Webster unabridged
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Time Traveler for pneumonitis
The first known use of pneumonitis was in 1817
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