ACT UP Synonyms: 58 Similar and Opposite Words

act up

verb

Definition of act up

as in to act out

to behave badly the two-year-old was acting up in church so much that her dad had to take her outside

Synonyms & Similar Words

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Antonyms & Near Antonyms

as in to cut up

to engage in attention-getting playful or boisterous behavior you should have seen the boys acting up when they put on their aprons

Synonyms & Similar Words

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 act up Baye continued acting up until 2023. — Kimberlee Speakman, PEOPLE, 18 Apr. 2026 The capsule’s toilet is already acting up. — Marcia Dunn, Chicago Tribune, 2 Apr. 2026 The black flies are not the only troublesome creature acting up during the unseasonably warm weather. — Clara Harter, Los Angeles Times, 28 Mar. 2026 Meanwhile, the guests, who have literally just arrived five minutes ago, are already acting up. — Rafaela Bassili, Vulture, 10 Mar. 2026 See All Example Sentences for act up

Recent Examples of Synonyms for act up

Verb

Men brought in from outside are coached to act out romances with her again and again, performing love, regret and guilt while their tears are gathered.

— Naman Ramachandran, Variety, 9 Oct. 2026
If Graham fails in her bid, she can be forgiven for acting out of loyalty and love for her brother.

— Kathleen Parker, Washington Post, 8 Oct. 2026

Definition of act out

Verb

Cityside, guests can head to the thumping heart of Austin nightlife where the Live Music Capital of the World always has a new favorite act and dance floor to cut up waiting just around the corner.

— Condé Nast, Condé Nast Traveler, 6 Oct. 2026
In July, the Public Service Commission requested utilities submit plans to cut up to 45% of savings from the program.

— Tom Nyein, Baltimore Sun, 3 Oct. 2026

Definition of cut up

Verb

The Utah Supreme Court ordered a new trial last year, pointing to misconduct by investigators.

— Landon Mion, FOXNews.com, 30 Sep. 2026
In addition, referees were instructed to apply the rules regarding fouls and misconducts more strictly – a move meant to protect players and their inventiveness.

— Cesar R. Torres, The Conversation, 26 May 2026

Definition of misconduct

Verb

The creditors’ lawsuit describes Kenny as a bullying presence who routinely threatened to fire anyone who disobeyed his orders.

— Nick Lichtenberg, Fortune, 1 Oct. 2026
Cops had issued summonses to the driver twice before, once in 2024 for failing to yield to a pedestrian and in 2018 for disobeying a traffic device, officials said.

— Rocco Parascandola, New York Daily News, 11 Sep. 2026

Definition of disobey

Verb

Also, don’t get too out of control horsing around with friends in the water.

— John Natale, Hartford Courant, 16 Aug. 2026
According to McGrady, the only royal who didn’t enjoy the time away in the Highlands was the late Princess Diana, who didn’t fit in with the family’s outdoorsy vibes and didn’t enjoy riding horses around the property due to a fall as a child.

— Meredith Kile, PEOPLE, 12 Aug. 2026

Definition of horse around

Browse Nearby Words

actuators

act up

acuity

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Cite this Entry

Style

“Act up.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/act%20up. Accessed 20 Oct. 2026.

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Synonyms of act up

verb

Example Sentences

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