behavior

noun

be·​hav·​ior bi-ˈhā-vyər How to pronounce behavior (audio)
bē-
Synonyms of behavior
1
: the way in which someone conducts oneself or behaves (see behave sense 1)
We were grateful for the gracious behavior of our hostess.
The children were rewarded for good behavior.
Be on your best behavior.
also : an instance of such behavior
unacceptable social behaviors
2
a
: the manner of conducting (see conduct entry 1 sense 2) oneself
criminal behavior
normal adolescent behavior
b
: anything that an organism does involving action and response to stimulation
c
: the response of an individual, group, or species to its environment
They are studying the behavior of elephants in the wild.
3
: the way in which something functions or operates
They tested the behavior of various metals under heat and pressure.

Synonyms of behavior

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Examples of behavior in a Sentence

I'm surprised by her bad behavior toward her friends. Students will be rewarded for good behavior. scientists studying the behavior of elephants An acceptable social behavior in one country may be unacceptable in another country. Doctors are trying to educate people about behaviors that can put them at increased risk for skin cancer. The experiment tested the behavior of various metals under heat and pressure.
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.
King was the same person before and after, even if her behaviors became less mysterious. — Laura Preston, New Yorker, 30 Aug. 2026 But if the reason you’re being drawn to improve your appearance comes from a place of in inadequacy and constant comparison to others, then this motivation may leave you at risk of developing restrictive or harmful behaviors. — Jennifer Donnelly, Scientific American, 30 Aug. 2026 Heading into the holidays, that tension between a willingness to spend and pressure on household budgets will likely shape consumer behavior. — Jill Standish, Forbes.com, 30 Aug. 2026 To test plasma behavior across temperature range American Fusion points out that these numbers are theoretical models of gross energy, not evidence of net electricity production. — Aman Tripathi, Interesting Engineering, 30 Aug. 2026 See All Example Sentences for behavior

Word History

Etymology

alteration of Middle English behavour, from behaven "to behave" + -our -or entry 2

First Known Use

15th century, in the meaning defined at sense 1

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

Phrases Containing behavior

Rhymes for behavior

See All Rhymes for behavior

Browse Nearby Words

behave
behavior
behavioral
See all Nearby Words

Cite this Entry

“Behavior.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/behavior. Accessed 1 Sep. 2026.

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Kids Definition

behavior

noun
be·​hav·​ior bi-ˈhā-vyər How to pronounce behavior (audio)
1
: the way in which one conducts oneself
2
: the way in which something (as a machine) behaves
3
: anything that a living being does that involves action and response to stimulation
behavioral
-vyə-rəl How to pronounce behavior (audio)
adjective

Medical Definition

behavior

noun
be·​hav·​ior
variants or chiefly British behaviour
bi-ˈhā-vyər How to pronounce behavior (audio)
1
: the manner of conducting oneself
2
a
: anything that an organism does involving action and response to stimulation
b
: the response of an individual, group, or species to its environment
behavioral adjective
or chiefly British behavioural
-vyə-rəl How to pronounce behavior (audio)
behaviorally adverb
or chiefly British behaviourally
-rə-lē How to pronounce behavior (audio)
Last Updated: - Updated example sentences
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