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

Caused by bacteria, Legionnaires' disease is a type of pneumonia. —Juan Carlos Castillo, Freep.com, 7 Aug. 2025

Legionnaires' disease is a severe form of pneumonia caused by Legionella bacteria, typically contracted through contaminated water or mist. —Chris Sims, IndyStar, 5 Aug. 2025

The affected individuals developed a severe form of pneumonia, which was later named Legionnaires’ disease. —Diana Leyva, Nashville Tennessean, 5 Aug. 2025

Scott Budinger, chief of pulmonary and critical care in the department of medicine, has spent more than two decades researching drugs to treat pneumonia. —Kate Armanini, Chicago Tribune, 5 Aug. 2025

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