reinforce

verb

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

intransitive verb

: to seek or get reinforcements
reinforceable
ˌrē-ən-ˈfȯr-sə-bəl How to pronounce reinforce (audio)
adjective

Synonyms of reinforce

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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.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The stretch is shutting down for construction of a reinforcing steel cage to support a bridge over the roadway. — Amaia Gavica, Miami Herald, 9 Oct. 2026 Like with Costco, greater price transparency could even reinforce TJX's value proposition. — Alexa Lomonaco, CNBC, 9 Oct. 2026 Then, though the process of preparing, learning and making this film, all those ideas have been reinforced even further. — Brian Davids, HollywoodReporter, 9 Oct. 2026 This season’s setting at the Musée Carnavalet reinforced the SMCP group brand’s alignment with French cultural heritage, but there was more substance here than atmosphere alone. — Rhonda Richford, Footwear News, 9 Oct. 2026 See All Example Sentences for reinforce

Word History

Etymology

re- + inforce, alteration of enforce

First Known Use

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

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

Rhymes for reinforce

See All Rhymes for reinforce

Browse Nearby Words

reinflation
reinforce
reinforced bow
See all Nearby Words

Cite this Entry

“Reinforce.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reinforce. Accessed 14 Oct. 2026.

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Kids Definition

reinforce

verb
re·​in·​force ˌrē-ən-ˈfō(ə)rs How to pronounce reinforce (audio)
-ˈfȯ(ə)rs
1
: to strengthen by additional assistance, material, or support
reinforce the elbows of a jacket
reinforce the argument with facts
2
: to strengthen or increase by fresh additions
were reinforcing their pitching staff
reinforce our troops
3
: to stimulate (a person or animal) with a reinforcer
also : to increase the frequency of (a response) with a reinforcer

Medical Definition

reinforce

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