in·​fect·​ed | \ in-ˈfek-təd How to pronounce infected (audio) \

Definition of infected

: having an infection : contaminated with an infective agent (such as a bacterium or virus) an infected wound Through a number of different means, these viruses persist at very low, hard-to-detect levels in infected cells.The Journal of the American Medical Association She explains that leptospirosis bacteria are shed in the urine of infected animals.— Tania Banak The fungus produces as many as 1 million conidia per square centimeter of infected leaf surface.— G. B. Lucas

First Known Use of infected

1534, in the meaning defined above

History and Etymology for infected

from past participle of infect

Keep scrolling for more

Learn More about infected

Time Traveler for infected

Time Traveler

The first known use of infected was in 1534

See more words from the same year

Statistics for infected

Last Updated

20 Jan 2021

Cite this Entry

“Infected.” Dictionary, Merriam-Webster, Accessed 25 Feb. 2021.

Style: MLA
MLA Chicago APA Merriam-Webster

Keep scrolling for more

More Definitions for infected



English Language Learners Definition of infected

: containing germs that cause disease
: having a disease caused by germs
: affected by a computer virus

Keep scrolling for more

Comments on infected

What made you want to look up infected? Please tell us where you read or heard it (including the quote, if possible).


Test Your Vocabulary

More Confusing Words—Quiz

  • cats on impossible timber
  • The magician ______ moved the selected card to the top of the deck.
Spell It

Can you spell these 10 commonly misspelled words?

 AlphaBear 2

Spell words. Make bears.

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!