beware

American  

[bih-wair] / bɪˈwɛər /

verb (used with object)

1. to be wary, cautious, or careful of (usually used imperatively).

   Beware such inconsistency. Beware his waspish wit.

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verb (used without object)

1. to be cautious or careful.

   Beware of the dog.

beware British  

/ bɪˈwɛə /

verb

1. to be cautious or wary (of); be on one's guard (against)

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Usage

What does beware mean? Beware means be careful or cautious—watch out for danger or other bad stuff. Beware is a command (or at least a suggestion). Sometimes, it’s used by itself, as in Beware! There are dark forces afoot! More commonly, it’s immediately followed by the specific thing you should beware of, as in Beware the words of politicians. Perhaps most commonly, it’s paired with the word of, such as on a sign that says Beware of cat. (You thought we were going to say Beware of dog, didn’t you? Stay alert, folks. Beware a wily dictionary.)Example: Before you enter the internet, there should be a sign that says “Beware of trolls.”

Etymology

Origin of beware

1150–1200; Middle English, from phrase of warning be ware. See be, ware ²

Explanation

To beware is to be cautious and on your guard. The riskier the situation, the more you need to beware. A "Beware of the dog" sign means there's a dog in the house who doesn't care for visitors or new people. When you beware, you become very cautious. You look both ways and use extreme caution. This word can be remembered if you break it into two parts: to beware is the same as "to be wary." When you're wary, you're concerned and careful. People in dangerous jobs like the police and fire department need to beware every day.

Example Sentences

But beware of viewing nuclear as an energy panacea.

From BBC • Apr. 3, 2026

But things change, and beware of Matsumoto, the pitcher.

From Los Angeles Times • Apr. 1, 2026

Plus, beware extra-long security lines and rising airfares.

From The Wall Street Journal • Mar. 14, 2026

Just beware that it’s quite possible a practical gift can backfire.

From MarketWatch • Feb. 13, 2026

The usurper Pelias had been told by an oracle that he would die at the hands of kinsmen, and that he should beware of anyone whom he saw shod with only a single sandal.

From "Mythology: Timeless Tales of Gods and Heroes" by Edith Hamilton

Related Words

• heed
• take care