be·​hav·​ior | \ bi-ˈhā-vyər How to pronounce behavior (audio) , 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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Synonyms for behavior


actions, address, bearing, comportment, conduct, demeanor, deportment, geste (also gest) [archaic]

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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.
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Recent Examples on the Web

Among the board members taking the Women’s March into a new era: Lucy Flores, who was one of the first to publicly discuss Joe Biden’s behavior with women and Native Americans in Philanthropy CEO Sarah Eagle Heart. Fortune, "Indra Nooyi: ‘We Need Our Own Sisterhood’," 17 Sep. 2019 All of this makes Theo’s behavior somewhat opaque, making him impossible to care for as a character. Stephanie Zacharek, Time, "The Goldfinch Is a Handsome Movie, But It Lies Flat as a Painting," 13 Sep. 2019 Hillary Clinton‘s campaign in 2016 chose the latter course, focusing on the most outlandish aspects of Trump’s behavior and deliberately down-playing his ties to the Republican Party. David Lauter, Los Angeles Times, "Democrats are missing an opportunity to brand Trump as too conservative, poll suggests," 13 Sep. 2019 Climate change was created by human behavior, and humans can do something about it, Harris said. Grace Segers, CBS News, "Democrats clash on health care and immigration in third debate," 13 Sep. 2019 To be clear, Brown’s behavior was mostly self-absorbed nonsense, save for the threat against Mayock. Ann Killion,, "Was Antonio Brown saga a ploy? A Patriots game? Or just Raiders as usual?," 7 Sep. 2019 Taken together, their stories reinforce a picture of an industry in which Domingo’s behavior was an open secret and young women were left to fend for themselves in the workplace. Jocelyn Gecker And Jocelyn Noveck, USA TODAY, "11 more women accuse opera singer Placido Domingo of sexual harassment, inappropriate behavior," 5 Sep. 2019 Dixon kicked things off by expressing her frustrations with Bryant’s behavior at the open house, which Dixon was staging for her first flipped property. Dave Quinn,, "RHOP's Gizelle Bryant Apologizes to Robyn Dixon for Open House Fight: 'I Really Messed Up'," 25 Aug. 2019 Wind has driven much of the fire’s rapid growth and erratic behavior, which prompted several rounds of evacuation orders for towns in Lassen and Plumas counties. Alex Wigglesworth, Los Angeles Times, "See images of the massive Walker fire from space," 16 Sep. 2019

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

8 Oct 2019

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 How to pronounce behavior (audio) \

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 How to pronounce behaviour (audio) \

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 How to pronounce behavioural (audio) \ adjective
behaviorally or chiefly British behaviourally \ -​rə-​lē How to pronounce behaviourally (audio) \ 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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