behavior

American  

[bih-hayv-yer] / bɪˈheɪv jər /

especially British, behaviour

noun

• behaviors
  plural

1. 

   manner of behaving or acting.

   Synonyms:

   carriage, bearing, demeanor

2. Psychology, Animal Behavior.

   1. observable activity in a human or animal.

   2. the aggregate of responses to internal and external stimuli.

   3. a stereotyped, species-specific activity, as a courtship dance or startle reflex.

3. Often behaviors. a behavior pattern.

4. the action or reaction of any material under given circumstances.

   the behavior of tin under heat.

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behavior Scientific  

/ bĭ-hāv′yər /

1. The actions displayed by an organism in response to its environment.

2. One of these actions. Certain animal behaviors (such as nest building) result from instinct, while others (such as hunting) must be learned.

3. The manner in which a physical system, such as a gas, subatomic particle, or ecosystem, acts or functions, especially under specified conditions.

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behavior Idioms  

1. see on one's best behavior.

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Synonym Usage

Behavior, conduct, deportment, comportment refer to one's actions before or toward others, especially on a particular occasion. Behavior refers to actions usually measured by commonly accepted standards: His behavior at the party was childish. Conduct refers to actions viewed collectively, especially as measured by an ideal standard: Conduct is judged according to principles of ethics. Deportment is behavior related to a code or to an arbitrary standard: Deportment is guided by rules of etiquette. The teacher gave Susan a mark of B in deportment. Comportment is behavior as viewed from the standpoint of one's management of one's own actions: His comportment was marked by a quiet assurance.

Other Word Forms

Derived Forms

• interbehavior
  noun
• behavioral
  adjective

Inflected Forms

Nouns

• behaviors
  plural

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Etymology

Origin of behavior

First recorded in 1375–1425; behave ( def. ) + -ior (on model of havior, variant of havor, from Middle French (h)avoir “a having,” ultimately from Latin habēre “to have”); replacing late Middle English behavoure, behaver; see -or ¹ ( def. )

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Explanation

Behavior refers to how you conduct yourself. Generally, it’s wise to engage in good behavior, even if you're really bored. The noun behavior is a spin-off of the verb behave. Get rid of the be in behave and you're left with have, which makes sense: you could say that to behave is to "have" or "own" yourself — to control yourself. There's also a broader definition of behavior, which is basically anything any living thing does in any situation. Brushing your teeth? Behavior. Scratching your nose? Behavior. Eating a large antelope because you are a lion and you're hungry? Also behavior.

Example Sentences

See Examples For:

behavior behaviors

By revealing how hidden atomic structures affect a material's behavior, the technique could provide valuable insights across materials science.

From Science Daily ● Oct. 25, 2026

Each clone consists of cancer cells with similar genetic characteristics, but their behavior can differ dramatically.

From Science Daily ● Oct. 25, 2026

Anthropic’s October Usage Policy Update included a section prohibiting “sustained and needless abusive or cruel behavior toward our models.”

From MarketWatch ● Oct. 24, 2026

Patel, the Brookings analyst and a former Postal Regulatory Commission employee, said that more direct communication to voters could have helped change their behavior.

From Salon ● Oct. 24, 2026

In your brain, Broca's area may let you speak and Wernicke's area may let you understand, but listening is also a complicated social behavior.

From "Phineas Gage" by John Fleischman

Innovative behaviors and precise muscular coordination can open up entirely new possibilities, allowing creatures to accomplish feats that their body shapes might initially suggest are impossible.

From Science Daily ● Oct. 24, 2026

Underneath these uncannily humanlike behaviors, could AI models also have inner lives and emotions?

From MarketWatch ● Oct. 24, 2026

The scientists also identified important differences in when certain progenitor cell characteristics and behaviors emerge during development.

From Science Daily ● Oct. 22, 2026

Laura stayed with Carl, she writes, because she felt she saw that he was sincerely working to change his behaviors and committed to regaining her trust.

From The Wall Street Journal ● Oct. 19, 2026

Discuss what types of behaviors fall under each of the five categories.

From "Music and the Child" by Natalie Sarrazin

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Related Words

• act
• action
• attitude
• conduct
• demeanor
• management
• nature
• performance
• practice
• presence
• role
• style

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