[ in-fek-shuhn ]
See synonyms for: infectioninfections on

  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.

  1. an infecting agency or influence.

  2. an infectious disease: Is this infection very dangerous?

  3. the condition of suffering an infection.

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

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

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

Origin of infection

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

Other words from infection

  • non·in·fec·tion, noun
  • post·in·fec·tion, adjective
  • pre·in·fec·tion, noun
  • re·in·fec·tion, noun
  • sub·in·fec·tion, noun

Words that may be confused with infection

Words Nearby infection Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

How to use infection in a sentence

British Dictionary definitions for infection


/ (ɪnˈfɛkʃən) /

  1. invasion of the body by pathogenic microorganisms

  2. the resulting condition in the tissues

  1. an infectious disease

  2. the act of infecting or state of being infected

  3. an agent or influence that infects

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

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

Scientific definitions for infection


[ ĭn-fĕkshən ]

  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. See also infectious disease opportunistic infection.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for infection


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

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.