on guard

phrase

Definition of on guardnext
as in alert
paying close attention usually for the purpose of anticipating approaching danger or opportunity Since it was hunting season, we wore brightly colored vests and remained on guard while hiking.

Synonyms & Similar Words

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Antonyms & Near Antonyms

Example Sentences

Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Recent Examples of on guard Disinformation and misinformation experts who spent years telling the public to be on guard against deepfakes are now trying to convince the public that the McConnell image is real. — David A. Graham, The Atlantic, 15 July 2026
Recent Examples of Synonyms for on guard
on the ball
Phrase
  • The 22-year-old, who stands at 6ft 3in, has pace and is comfortable on the ball, but is also has a strong aerial presence.
    — Paul Taylor, New York Times, 1 Aug. 2026
  • Catcher Daniel Susac pounced on the ball and delivered a perfect strike to second base.
    — Justice delos Santos, Mercury News, 21 July 2026
Definition of on the ball

Browse Nearby Words

ongoing
on guard
on hand
See all Nearby Words

Cite this Entry

“On guard.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/on%20guard. Accessed 2 Aug. 2026.

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