behavior

noun

be·​hav·​ior bi-ˈhā-vyər How to pronounce behavior (audio)
bē-
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.

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.
Tahlequah previously made global headlines in 2018 for carrying a dead calf for over 1,000 miles across 17 days, demonstrating what researchers believe is mourning behavior among orcas. Adeola Adeosun, MSNBC Newsweek, 16 Sep. 2025 This defensive mindset leads to noticeable changes in workplace behavior. Kara Dennison, Forbes.com, 16 Sep. 2025 Mentored youth also saw lower absenteeism rates, fewer school suspensions and improved behaviors. Lina Ruiz september 16, Fort Worth Star-Telegram, 16 Sep. 2025 Over the years, his legacy has been clouded by reports of difficult behavior, as well as the author’s own history of antisemitic remarks, which his family publicly apologized for in 2020. Dave Quinn, PEOPLE, 16 Sep. 2025 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

Browse Nearby Words

Cite this Entry

“Behavior.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/behavior. Accessed 18 Sep. 2025.

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 adjective

Medical Definition

behavior

noun
be·​hav·​ior
variants or chiefly British behaviour
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
behaviorally adverb
or chiefly British behaviourally

More from Merriam-Webster on behavior

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