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 scorching temperatures and persistent droughts in June and July mutually reinforced each other to create a hot weather spiral, according to Samantha Burgess, strategic lead for climate at the European Centre for Medium-Range Weather Forecasts. — Lex Harvey, CNN Money, 10 Aug. 2026 Furthermore, the discovery reinforces Rio Grande do Sul’s status as one of the world’s most important regions for the study of Triassic fauna. — The Conversation, Fortune, 10 Aug. 2026 That’s reinforced by discovery habits as well, with 61% of Gen Z now favoring in‑person browsing for new products—up sharply over the past year. — Andrew Stern, Forbes.com, 10 Aug. 2026 The grants help pay for home improvements like upgrading roof coverings, retrofitting doors and windows, and reinforcing connections between walls and roofs. — Jaclyn De Medicci Bruneau, Sun Sentinel, 9 Aug. 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 11 Aug. 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

More from Merriam-Webster on reinforce

Nglish: Translation of reinforce for Spanish Speakers

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