behave

American  

[bih-heyv] / bɪˈheɪv /

verb (used without object)

behaved, behaving

1. to act in a particular way; conduct or comport oneself or itself.

   The ship behaves well.

   Synonyms:

   perform

2. to act properly.

   Did the child behave?

3. to act or react under given circumstances.

   This plastic behaves strangely under extreme heat or cold.

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verb (used with object)

behaved, behaving

1. to conduct or comport (oneself ) in a proper manner.

   Sit quietly and behave yourself.

behave British  

/ bɪˈheɪv /

verb

1. (intr) to act or function in a specified or usual way

2. to conduct (oneself) in a specified way

   he behaved badly towards her

3. to conduct (oneself) properly or as desired

   the child behaved himself all day

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Other Word Forms

• unbehaving adjective
• well-behaved adjective

Etymology

Origin of behave

First recorded in 1400–50; late Middle English behaven “to behave oneself”; equivalent to be- + have

Example Sentences

“The real test will be how markets behave through the rest of the week, particularly given the recent pattern of selling into the weekend,” said Mark Hackett, chief markets strategist for Nationwide.

From Barron's • Apr. 1, 2026

When you don’t know the length of the runway, you behave differently.

From MarketWatch • Mar. 24, 2026

The error was particularly humiliating for companies focused on making AI behave according to human values and intentions, which is known as “alignment.”

From The Wall Street Journal • Mar. 24, 2026

The footage was gathered during fieldwork in the Azores and Balearic islands between 2020 and 2022, offering a rare look at how these animals behave near the ocean surface.

From Science Daily • Mar. 23, 2026

She knew she should behave, not draw any more attention to herself.

From "The Marvellers" by Dhonielle Clayton

Related Words

• act
• operate
• perform
• react