pneumonia

American  

[noo-mohn-yuh, -moh-nee-uh, nyoo-] / nʊˈmoʊn jə, -ˈmoʊ ni ə, njʊ- /

noun

Pathology.

pneumonia plural

1. inflammation of the lungs with congestion.

2. Also called lobar pneumonia.  an acute disease of the lungs, caused by the bacterium Streptococcus pneumoniae and characterized by fever, a cough with blood-tinged phlegm, and difficult breathing.

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pneumonia British  

/ njuːˈməʊnɪə /

noun

1. inflammation of one or both lungs, in which the air sacs (alveoli) become filled with liquid, which renders them useless for breathing. It is usually caused by bacterial (esp pneumococcal) or viral infection

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pneumonia Scientific  

/ n-mōn′yə /

1. An acute or chronic disease marked by inflammation of the lungs, especially an infectious disease caused by viruses, bacteria, or other pathogens, such as mycoplasmas. Individuals with pneumonia often have abnormal chest x-rays that show areas with fluid in the infected part of the lungs.

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pneumonia Cultural  

1. A disease characterized by inflammation of the lungs. Pneumonia can be caused by many factors, including bacterial infections, viral infections, and the inhalation of chemical irritants.

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Other Word Forms

Noun Inflected Forms

• pneumonia
  plural

Etymology

Origin of pneumonia

First recorded in 1595–1605; from New Latin, from Greek pneumonía; equivalent to pneumon- + -ia

Compare meaning

How does pneumonia compare to similar and commonly confused words? Explore the most common comparisons:

• atelectasis vs. pneumonia
• pleurisy vs. pneumonia
• ammonia vs. pneumonia

Explanation

Pneumonia is a lung infection that gives you a cough and a fever and generally makes it difficult to breathe. If you catch pneumonia, you may end up in the hospital. You've probably had people warn you not to go out in the rain without an umbrella or out in the cold without a hat or scarf because you’ll catch pneumonia. While they have your best interests in mind, you don’t actually get pneumonia from being cold or wet. Pneumonia is caused by viruses or bacteria. It’s a pretty common disease, but unfortunately it can be very serious in some cases, particularly in young children and elderly people.

Example Sentences

See Examples For:

pneumonia

He said that while hospitalized he also "had to deal with a mild case of pneumonia."

From Barron's ● Jul. 13, 2026

US Senator Mitch McConnell says he will not be returning to the Senate "quite yet" after suffering from a fall and "a mild case of pneumonia".

From BBC ● Jul. 12, 2026

Against that backdrop, influenza and pneumonia stood out—moving from 11th to eighth place in all age groups—with 56,511 deaths in 2025 compared with 48,139 in 2024.

From The Wall Street Journal ● Jul. 2, 2026

Keaton, who died from primary bacterial pneumonia at the age of 79, spent years meticulously renovating the Sullivan Canyon abode.

From MarketWatch ● Jun. 22, 2026

“You take him on out in de sun. You bofe get pneumonia down here on dis wet flo.”

From "The Sound and the Fury" by William Faulkner