pneumonia

noun

pneu·​mo·​nia nu̇-ˈmō-nyə 

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

Put simply, when banks sneeze, the rest of the financial system catches pneumonia. — Mayra Rodriguez Valladares, Forbes.com, 29 Aug. 2026

The actor died Saturday in Los Angeles surrounded by loved ones after battling pneumonia, her family told The Times on Thursday. — Emily St. Martin, Los Angeles Times, 28 Aug. 2026

Children under the age of 5 who get measles are more likely to develop serious complications, including pneumonia and brain swelling, compared with older kids. — Brenda Goodman, CNN Money, 28 Aug. 2026

Siegel noted that measles weakens the immune system and increases the risk of pneumonia, which can stem from measles itself or from a secondary bacterial infection. — Melissa Rudy, FOXNews.com, 28 Aug. 2026

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

Phrases Containing pneumonia

• double pneumonia
• Pneumocystis carinii pneumonia
• primary atypical pneumonia
• walking pneumonia

Rhymes for pneumonia

• ammonia
• begonia
• bronchopneumonia
• pleuropneumonia

Kids Definition

pneumonia

noun

pneu·​mo·​nia n(y)u̇-ˈmō-nyə 

: 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 

: 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