re·​in·​force | \ ˌrē-ən-ˈfȯrs How to pronounce reinforce (audio) \
variants: or less commonly
reinforced also reenforced; reinforcing also reenforcing; reinforces also reenforces

Definition of reinforce

transitive verb

1 : to strengthen by additional assistance, material, or support : make stronger or more pronounced reinforce levees reinforce the elbows of a jacket reinforce ideas
2 : to strengthen or increase by fresh additions reinforce our troops were reinforcing their pitching staff
3 : to stimulate (a subject, such as an experimental animal) by reinforcement (see reinforcement sense 3) also : to encourage (a response) by reinforcement

Other Words from reinforce

reinforceable \ ˌrē-​ən-​ˈfȯr-​sə-​bəl How to pronounce reinforce (audio) \ adjective

Examples of reinforce in a Sentence

The captain sent out another squad to reinforce the troops. Our camp is reinforced with supplies flown in by helicopter. The levees will need to be reinforced. The bad weather forecast only reinforces our decision to leave early tomorrow. Some critics say that the movie reinforces negative stereotypes about the military. We do our best to reinforce good conduct in the classroom. See More
Recent Examples on the Web The story infuses and connects each stage of the buyer’s journey and aligns every touchpoint, which helps reinforce the narrative. Marie Hattar, Forbes, 9 June 2022 Dressing up in outfits that reinforce racist stereotypes also counts as blackface. Lizz Schumer, Good Housekeeping, 6 June 2022 Methods to increase connectedness include classroom management techniques that reinforce attentive, cooperative and collaborative behaviors, reduce peer victimization and help youth understand how others feel and behave. Mitch Prinstein, Scientific American, 31 May 2022 There are moments when War Pony sags — the result of one too many scenes of filler and a few sequences that reinforce facile observations about how Native culture is treated by white people. Lovia Gyarkye, The Hollywood Reporter, 21 May 2022 Crypto evangelists tend to see meltdowns like Terra's as an unfortunate loss, but one that ultimately helps reinforce the credibility of the underlying blockchain technology. Allison Morrow, CNN, 12 May 2022 But having grandparents that reinforce the idea that a Eurocentric standard of beauty is better will plant seeds of insecurity., 12 May 2022 Urging rank-and-file Republicans to work as poll watchers plays on their fears of voter fraud and helps reinforce party loyalty, G.O.P. officials say. New York Times, 15 Jan. 2022 That road, connecting Kramatorsk to Severodonetsk via Siversk, has allowed Kyiv to reinforce and resupply its troops in and around Severodonetsk. David Axe, Forbes, 6 June 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'reinforce.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of reinforce

15th century, in the meaning defined at transitive sense 1

History and Etymology for reinforce

re- + inforce, alteration of enforce

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Time Traveler for reinforce

Time Traveler

The first known use of reinforce was in the 15th century

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Dictionary Entries Near reinforce



reinforced bow

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Statistics for reinforce

Last Updated

30 Jun 2022

Cite this Entry

“Reinforce.” Dictionary, Merriam-Webster, Accessed 3 Jul. 2022.

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More Definitions for reinforce


re·​in·​force | \ ˌrē-ən-ˈfȯrs \
reinforced; reinforcing

Kids Definition of reinforce

1 : to strengthen with new supplies or more people Another squad reinforced the troops.
2 : to strengthen by adding more material for support The wall needs to be reinforced.


transitive verb
re·​in·​force | \ ˌrē-ən-ˈfō(ə)rs, -ˈfȯ(ə)rs How to pronounce reinforce (audio) \
reinforced; reinforcing

Medical Definition of reinforce

1 : to strengthen by additional material or support : make stronger reinforced with vitamins
2 : to stimulate (as an experimental animal or a student) by reinforcement also : to encourage (a response) by reinforcement

Other Words from reinforce

reinforceable \ -​ə-​bəl How to pronounce reinforce (audio) \ adjective

More from Merriam-Webster on reinforce

Nglish: Translation of reinforce for Spanish Speakers

Britannica English: Translation of reinforce for Arabic Speakers


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