pneumonia

noun

pneu·​mo·​nia nu̇-ˈmō-nyə How to pronounce pneumonia (audio)
nyu̇-
: an acute disease that is marked by inflammation of lung tissue accompanied by infiltration of alveoli and often bronchioles with white blood cells (such as neutrophils) and fibrinous exudate, is characterized by fever, chills, cough, difficulty in breathing, fatigue, chest pain, and reduced lung expansion, and is typically caused by an infectious agent (such as a bacterium, virus, or fungus) see bronchopneumonia, pneumocystis carinii pneumonia, primary atypical pneumonia compare pneumonitis

Examples of pneumonia in a Sentence

He caught pneumonia over the winter.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The panelists hold three open meetings each year to assess and vote on the clinical use of various existing and new vaccines, including ones that protect people against pneumonia, chicken pox, shingles, measles, mumps and rubella (MMR), polio, respiratory syncytial virus (RSV), influenza and COVID. Lauren J. Young, Scientific American, 10 June 2025 In the early 1900s, improved public health brought about a major shift: Deaths from infectious illnesses like pneumonia, tuberculosis and diphtheria declined. Scott Braunstein, Forbes.com, 9 June 2025 She was diagnosed as having bronchial pneumonia and spent the next two weeks in bed. Jim Shepard, New Yorker, 8 June 2025 Ten percent, 20% of kids are being hospitalized, measles, pneumonia, neurologic injury. Asuka Koda, CNN Money, 5 June 2025 See All Example Sentences for pneumonia

Word History

Etymology

New Latin, from Greek, from pneumōn lung, alteration of pleumōn — more at pulmonary

First Known Use

1603, in the meaning defined above

Time Traveler
The first known use of pneumonia was in 1603

Browse Nearby Words

Cite this Entry

“Pneumonia.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pneumonia. Accessed 18 Jun. 2025.

Kids Definition

pneumonia

noun
pneu·​mo·​nia n(y)u̇-ˈmō-nyə How to pronounce pneumonia (audio)
: a disease of the lungs marked by inflammation, congestion, fever, cough, and difficulty in breathing and caused especially by infection

Medical Definition

pneumonia

noun
pneu·​mo·​nia n(y)u̇-ˈmō-nyə How to pronounce pneumonia (audio)
: an acute disease that is marked by inflammation of lung tissue accompanied by infiltration of alveoli and often bronchioles with white blood cells (as neutrophils) and fibrinous exudate, is characterized by fever, chills, cough, difficulty in breathing, fatigue, chest pain, and reduced lung expansion, and is typically caused by an infectious agent (as a bacterium, virus, or fungus) see bronchopneumonia, lobar pneumonia, pneumocystis carinii pneumonia, primary atypical pneumonia

More from Merriam-Webster on pneumonia

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