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be on guard

VERB
look out
Synonyms
WEAK
be alert be careful 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
VERB
mind
Synonyms
STRONGEST
tend
STRONG
trouble watch
WEAK
be cautious be concerned be solicitous be wary have a care mind one's p's and q's take care toe the line watch one's step watch out
Antonyms
WEAK
disregard forget 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.

Still, banks also flagged plenty of reasons to be on guard.

From The Wall Street Journal • Apr. 15, 2026

Flynn warned that it’s safer “to be on guard for any outcome over the weekend” — although risk could go either way.

From MarketWatch • Feb. 6, 2026

The sense of fear is palpable in parts of northern Japan, where some locals have fastened bells to their bags hoping the noise will keep bears away, while signs warn people to be on guard.

From Barron's • Nov. 8, 2025

There is no disputing that anyone with a phone or computer has to be on guard at all times.

From Los Angeles Times • Jun. 24, 2023

Still, it’s tiring to always be on guard, always peering out the window, looking over my shoulder.

From "The Queen of Water" by Laura Resau