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Dictionary.com

be alert

VERB
look out
Synonyms
WEAK
be careful be on guard beware check out have a care heads up hearken keep an eye out keep tabs listen mind notice pay attention peg pick up on scope shotgun size up spot spy watch out
Antonyms
WEAK
disregard ignore neglect

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.

The Met had earlier promised an increased police presence in response to the protest, adding officers would be "alert to any behaviour that crosses the line from protest into criminality".

From BBC • Mar. 28, 2026

“We have to be alert to second round effects but there are risks on both sides.”

From The Wall Street Journal • Mar. 26, 2026

Though current risks from stablecoins were "limited", the economists said, their "rapid growth" meant regulators had to be alert to potential dangers.

From Barron's • Nov. 24, 2025

“Directors should be alert and speak up is all that I can advise.”

From The Wall Street Journal • Nov. 10, 2025

I much preferred to be alert and clearheaded.

From "Americanized" by Sara Saedi