[ ree-in-fawrs, -fohrs ]
See synonyms for reinforce on
verb (used with object),re·in·forced, re·in·forc·ing.
  1. to strengthen with some added piece, support, or material: to reinforce a wall.

  2. to strengthen (a military force) with additional personnel, ships, or aircraft: to reinforce a garrison.

  1. to strengthen; make more forcible or effective: to reinforce efforts.

  2. to augment; increase: to reinforce a supply.

  3. Psychology. to strengthen the probability of (a response to a given stimulus) by giving or withholding a reward.

  1. something that reinforces.

  2. a metal band on the rear part of the bore of a gun, where the explosion occurs.

Origin of reinforce

First recorded in 1590–1600; re- + inforce, alteration of enforce
  • Also re·en·force, re-en·force [ree-uhn-fawrs, -fohrs] /ˌri ənˈfɔrs, -ˈfoʊrs/ .

Other words from reinforce

  • re·in·forc·er, noun
  • self-re·in·forc·ing, adjective
  • un·re·in·forced, adjective Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

British Dictionary definitions for reinforce


/ (ˌriːɪnˈfɔːs) /

  1. to give added strength or support to

  2. to give added emphasis to; stress, support, or increase: his rudeness reinforced my determination

  1. to give added support to (a military force) by providing more men, supplies, etc

  2. psychol to reward an action or response of (a human or animal) so that it becomes more likely to occur again

Origin of reinforce

C17: from obsolete renforce, from French renforcer; see re- + inforce enforce

Derived forms of reinforce

  • reinforcement, noun

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