infection

American  

[in-fek-shuhn] / ɪnˈfɛk ʃən /

noun

• infections
  plural

1. an act or fact of infecting; state of being infected.

2. an infecting with germs of disease, as through the medium of infected insects, air, water, or clothing.

3. an infecting agency or influence.

4. an infectious disease.

   Is this infection very dangerous?

5. the condition of suffering an infection.

6. corruption of another's opinions, beliefs, moral principles, etc.; moral contamination.

7. an influence or impulse passing from one to another and affecting feeling or action.

8. Grammar. (in Celtic languages) assimilation in which a vowel is influenced by a following vowel or semivowel; umlaut.

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infection British  

/ ɪnˈfɛkʃən /

noun

1. invasion of the body by pathogenic microorganisms

2. the resulting condition in the tissues

3. an infectious disease

4. the act of infecting or state of being infected

5. an agent or influence that infects

6. persuasion or corruption, as by ideas, perverse influences, etc

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infection Scientific  

/ ĭn-fĕk′shən /

1. The invasion of the body of a human or an animal by a pathogen such as a bacterium, fungus, or virus. Infections can be localized, as in pharyngitis, or widespread as in sepsis, and are often accompanied by fever and an increased number of white blood cells. Individuals with immunodeficiency syndromes are predisposed to certain infections.

2. See also infectious disease opportunistic infection

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infection Cultural  

1. Invasion of the body or a body part by a pathogenic organism, which multiplies and produces harmful effects on the body's tissues.

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Other Word Forms

Derived Forms

• noninfection
  noun
• preinfection
  noun
• reinfection
  noun
• subinfection
  noun
• postinfection
  adjective

Inflected Forms

Nouns

• infections
  plural

Etymology

Origin of infection

1350–1400; Middle English infeccio ( u ) n < Late Latin infectiōn- (stem of infectiō ). See infect, -ion

Explanation

Infections are what happens when germs invade your body and cause a disease. Some, like meningitis, an infection of the tissues covering the brain and spinal cord, can be deadly. Others, like the common cold, are relatively mild. If you've ever scraped your knee and ended up with a swollen, achy scab, you know that you can develop an infection if you don't tend to your cuts and wounds and keep them clean. Though the word was traditionally used in the medical sense to refer to the pathogens, or germs, that cause illness, infection is now sometimes used in a broader sense to refer to people or things that act like pathogens. If rival gangs turn a neighborhood into a battleground, you could refer to this as an infection of gang activity.

Example Sentences

See Examples For:

infection infections

C3 and similar proteins evolved to protect the body against infection.

From Science Daily ● Aug. 26, 2026

However, human infection is rare and typically only causes mild symptoms.

From Science Daily ● Aug. 24, 2026

Paul's strokes were brought on by a sepsis infection, which he caught after cutting his thumb at work.

From BBC ● Aug. 20, 2026

Of 1,306 patients, 35.9% met “fire-related exposure criteria,” meaning they showed symptoms such as an acute upper respiratory infection, eye disorder, conjunctivitis, cough, asthma exacerbation or other respiratory problem.

From Los Angeles Times ● Aug. 20, 2026

Many American doctors, including Garfield's, still refused to accept that microbes caused infection.

From "Ambushed!" by Gail Jarrow

The researchers say the findings could now support dietary intervention studies involving people with obesity, chronic infections, and other conditions associated with weakened immune function.

From Science Daily ● Aug. 22, 2026

Public Health Department has recorded 15 infections so far this year, with roughly half in the San Fernando Valley.

From Los Angeles Times ● Aug. 21, 2026

Evatt started treatment in March 2020, around the same time that the rest of the world was learning about Moderna and its mRNA-based vaccines, and whether they could prevent COVID-19 infections.

From MarketWatch ● Aug. 20, 2026

In the current outbreak most infections do not seem to arise from food that has cooked at home.

From BBC ● Aug. 19, 2026

We know, too, that the antimosquito breeding campaigns in Cuba and Panama were very effective in halting the infections and that massive insecticide campaigns can control the populations of Aedes aegypti.

From "An American Plague: The True and Terrifying Story of the Yellow Fever Epidemic of 1793" by Jim Murphy

Related Words

• bug
• disease
• epidemic
• flu
• pollution
• virus