reinforce

verb

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

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
reinforceable 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.
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 goal isn’t to separate the machine from the workforce, but to build an inclusive system where the two operate together, reinforcing each other’s strengths. Priya Vijayarajendran, Forbes.com, 30 June 2025 Scaring a black bear can reinforce its natural fear of people and help keep it from lingering in neighborhoods and other areas where conflicts often arise. Stephen Underwood, Hartford Courant, 30 June 2025 As the fireline is constructed, inspected or reinforced, mappers record those details to adjust the containment percentage. Ca Wildfire Bot, Sacbee.com, 30 June 2025 The family also played a key role in commemorating the 80th anniversaries of D-Day and V-E Day, further reinforcing its role on both the national and international stage. Gabe Whisnant, MSNBC Newsweek, 30 June 2025 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

Browse Nearby Words

Cite this Entry

“Reinforce.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/reinforce. Accessed 4 Jul. 2025.

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
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 adjective

More from Merriam-Webster on reinforce

Last Updated: - Updated example sentences
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