infection

[in-fek-shuhn]

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.

infection

/ 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

infection

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

infection

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

Other Word Forms

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

Word History and Origins

Origin of infection¹

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

Example Sentences

On Monday three scientists' work on how the immune system attacks hostile infections won them the prize for medicine.

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A cough can result from either infection or an allergic reaction.

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Dr Ramsdell, along with two other scientists, won the prize for their research into how the immune system attacks hostile infections.

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In a video about her absence, she explained the “little problem,” noting the kidney stone had led to an infection and that it was doctor’s orders to stay put.

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The Nobel Prize in Physiology or Medicine 2025 has been awarded for discoveries that explain how the immune system attacks hostile infections, but not the body's own cells.

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Related Words

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