verb (used with object)

verb (used without object)

to become infected.


Archaic. infected.

Nearby words

  1. infatuated,
  2. infatuation,
  3. infauna,
  4. infeasibility,
  5. infeasible,
  6. infected,
  7. infected abortion,
  8. infectee,
  9. infection,
  10. infection immunity

Origin of infect

1350–1400; Middle English infecten < Latin infectus (past participle of inficere to immerse in dye, discolor, taint, poison), equivalent to in- in-2 + -fec-, combining form of facere to do1, make (see fact) + -tus past participle suffix

Related forms
Can be confusedafflict infect inflictinfect infest invest Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for infect

British Dictionary definitions for infect


verb (mainly tr)

to cause infection in; contaminate (an organism, wound, etc) with pathogenic microorganisms
(also intr) to affect or become affected with a communicable disease
to taint, pollute, or contaminate
to affect, esp adversely, as if by contagion
computing to affect with a computer virus
mainly international law to taint with crime or illegality; expose to penalty or subject to forfeiture


archaic contaminated or polluted with or as if with a disease; infected
Derived Formsinfector or infecter, noun

Word Origin for infect

C14: from Latin inficere to dip into, stain, from facere to make

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

Word Origin and History for infect



late 14c., from Latin infectus, past participle of inficere "to spoil, stain," literally "to put in to, dip into," from in- "in" (see in- (2)) + facere "perform" (see factitious). Related: Infected; infecting.

Online Etymology Dictionary, © 2010 Douglas Harper

Medicine definitions for infect




To contaminate with a pathogenic microorganism or agent.
To communicate a pathogen or disease to another organism.
To invade and produce infection in an organ or body part.

The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.