pneumonia

American  

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

noun

Pathology.

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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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

The most severe form of Legionella bacteria infection leads to Legionnaires’ disease, a serious and potentially deadly type of pneumonia, the CDC says.

From Los Angeles Times • May 18, 2026

She had a broken back, typhoid fever, pneumonia and pleurisy.

From The Wall Street Journal • May 14, 2026

A German woman who had a fever on April 28, and later developed pneumonia, died on May 2 on board the ship.

From Barron's • May 11, 2026

According to the WHO, the woman initially developed a fever on 28 April and eventually presented with symptoms of pneumonia.

From BBC • May 8, 2026

“I’ve seen worse ones get well. If he doesn’t get pneumonia, we’ll pull him through. You stay with him. If he gets worse, you can come and get me.”

From "The Red Pony" by John Steinbeck