infection

American  

[in-fek-shuhn] / ɪnˈfɛk ʃən /

noun

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

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

Etymology

Origin of infection

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

Example Sentences

His 10th place there was seemingly excused as a minor infection was identified afterwards.

From BBC • Apr. 9, 2026

Inside the body, this process is driven by immune cells that release chemical signals to respond to injury or infection.

From Science Daily • Apr. 9, 2026

Endemicity is when an infection is constantly present, like the common cold.

From Salon • Apr. 8, 2026

The Los Angeles County medical examiner said the cause of death stemmed from the combined effects of physical exertion, environmental heat exposure, blunt trauma and COVID-19 infection.

From Los Angeles Times • Apr. 6, 2026

After a couple of days of rest and some antibiotics, what indeed had turned out to be a nasty ear infection for Malia cleared up, returning our toddler to her normal bouncy state.

From "Becoming" by Michelle Obama

Related Words

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