behavior

American  

[bih-heyv-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

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. )

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

He managed to get through his entire book tour, including a stint on “The View,” without clips of his awkward behavior going viral.

From Salon ● Jul. 29, 2026

The device was primarily designed to investigate fundamental physics and demonstrate a behavior that had never previously been observed.

From Science Daily ● Jul. 28, 2026

For some brands, advocacy programs allow them to gain control of an online behavior taking place organically.

From The Wall Street Journal ● Jul. 27, 2026

However, the 6-foot-5, 260-pound Adongo began exhibiting increasingly erratic behavior.

From Los Angeles Times ● Jul. 27, 2026

Any damage to the frontal cortex can change behavior and personality forever, as the case of Phineas Gage demonstrates.

From "Phineas Gage" by John Fleischman

The hypothesis itself arose from observations of grandmothers’ behaviors in extant hunter-gatherer groups in the 1980s.

From The Wall Street Journal ● Jul. 28, 2026

But romance is different from other trackable behaviors like sleep or flatulence.

From The Wall Street Journal ● Jul. 27, 2026

Breaking the carcass into smaller portions would make it easier for a calf or juvenile to feed, which is consistent with other known orca behaviors.

From Science Daily ● Jul. 23, 2026

Violence is shaped by social norms, power dynamics and the behaviors that institutions reward, tolerate or condemn.

From Salon ● Jul. 18, 2026

A preschool teacher had noted certain worrying behaviors in their four-year-old son, Nicholas, and suggested he needed testing.

From "The Big Short" by Michael Lewis

Related Words

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