Dictionary.com
Thesaurus.com

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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

pneumonia Scientific  
/ n-mōnyə /
  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.


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.


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:

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.

Keep Reading on Vocabulary.com

Vocabulary lists containing pneumonia

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Pneumonia is what most often sends a child with measles to hospital.

From Salon • Mar. 11, 2025

Pneumonia, urinary tract infections, sepsis: diseases like these can become fatal without antibiotics.

From Science Daily • Feb. 1, 2024

Beloved New Orleans session musician backed Little Richard and others and recorded his party favorites like “Rockin’ Pneumonia and the Boogie Woogie Flu.”

From Seattle Times • Dec. 31, 2023

Pneumonia, influenza and COVID-19 also accounted for 11% of all deaths in the county that week — also an increase from the previous week.

From Los Angeles Times • Dec. 9, 2022

Pneumonia today is not what it once was, especially when I had it.

From "The Princess Bride" by William Goldman