be·hav·ior | \ bi-ˈhā-vyər , bē- \

Definition 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

2a : 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.

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Other words from behavior

behavioral \bi-ˈhā-vyə-rəl, bē- \ adjective
behaviorally \bi-ˈhā-vyə-rə-lē, bē- \ adverb

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.
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Recent Examples on the Web

This is a mistake because bad behavior by executives is evidence of weak governance and a flawed corporate culture. Elizabeth Winkler, WSJ, "#MeToo Is Not a Buying Opportunity for Investors," 12 July 2018 Cruz had repeatedly shown signs of disturbing behavior. Lisa J. Huriash,, "Schools should set up 'threat teams' to prevent massacres, Secret Service says," 12 July 2018 For instance, the weird behavior of SpaceX’s liquid oxygen propellant led to one of the company’s Falcon 9 rockets exploding on a launchpad in 2016. Loren Grush, The Verge, "Europe will fire its record-setting big solid rocket motor this week," 11 July 2018 Police said Kinner had recently been asked to leave the apartment complex because of bad behavior., "Refugee who fled violence mourns daughter slain in Idaho," 4 July 2018 Just as in real life, bad behavior by thoughtless people has followed us into the online universe. Dwight Silverman, San Antonio Express-News, "How to be a good internet citizen," 3 July 2018 The study participants read short accounts of violent behavior: In one, a man smashed a beer bottle over someone’s head; in another, an assailant raped an acquaintance. Sharon Begley, STAT, "Can zapping people’s brains reduce violence? Controversial study sees potential," 2 July 2018 The Chicago Tribune reported in 2016 that Farquhar had been accused — though never charged or convicted — of aggressive behavior in the past. Alicia Fabbre, Daily Southtown, "Ex-Monee mayor who was accused of breaking ump's jaw at youth baseball game pleads guilty to aggravated battery, records show," 29 June 2018 But her mind keeps slipping out of control, erupting into the kind of anti-social behavior that keeps her from getting her daughter back. Deborah Young, The Hollywood Reporter, "'Bikini Moon': Film Review | Shanghai 2018," 27 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'behavior.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of behavior

15th century, in the meaning defined at sense 2a

History and Etymology for behavior

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

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Statistics for behavior

Last Updated

10 Sep 2018

Look-up Popularity

Time Traveler for behavior

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

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More Definitions for behavior



English Language Learners Definition of behavior

: the way a person or animal acts or behaves

: the way something (such as a machine or substance) moves, functions, or reacts


be·hav·ior | \ bi-ˈhāv-yər \

Kids Definition of behavior

1 : the manner in which a person acts Students are rewarded for good behavior.

2 : the whole activity of something and especially a living being Scientists observed the elephant's behavior.


variants: or chiefly British behaviour \bi-ˈhā-vyər \

Medical Definition of behavior 

1 : the manner of conducting oneself

2a : anything that an organism does involving action and response to stimulation

b : the response of an individual, group, or species to its environment

Other words from behavior

behavioral or chiefly British behavioural \-vyə-rəl \ adjective
behaviorally or chiefly British behaviourally \-rə-lē \ adverb

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More from Merriam-Webster on behavior

Thesaurus: All synonyms and antonyms for behavior

Spanish Central: Translation of behavior

Nglish: Translation of behavior for Spanish Speakers

Britannica English: Translation of behavior for Arabic Speakers

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to make amends

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