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Synonyms

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.


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)

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“But buyer beware: The data that you may be licensing might already be subject to copyright.”

From The Wall Street Journal • Apr. 3, 2026

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

From Los Angeles Times • Apr. 1, 2026

"So, AI should beware - for this week's predictions I've been gazing at where his hut used to be and thinking 'what would Albert do?'"

From BBC • Feb. 26, 2026

But investors beware: The race to increase production risks creating an eventual glut of hardware and a painful crash.

From Barron's • Feb. 23, 2026

‘Did I not say to you: if you pass the doors of Moria, beware? Alas that I spoke true! What hope have we without you?’

From "The Fellowship of the Ring" by J.R.R. Tolkien