act up

verb

Definition of act upnext
1
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
2
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
  1. act out
  2. cut up
  3. misconduct
  4. show off
  5. disobey
  6. horse around
  7. carry on
Verb
  • Likewise, Duong used her cameras to create a safe space for her family to act out past memories to, at long last, talk about what each means to one another, good and bad.
    — Etan Vlessing, HollywoodReporter, 4 Oct. 2026
  • Some of the stories are just spoken matter-of-factly, while others are acted out with Jaku doing all the voices.
    — Christopher Arnott, Hartford Courant, 2 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
  • Heather immediately shows off her Japanese with the hotel manager.
    — Louis Peitzman, Vulture, 9 Oct. 2026
  • Keri Russell once again showed off her impressive foot arch in a dramatically steep pair of minimalist mules.
    — Karla Rodriguez, Footwear News, 9 Oct. 2026
Definition of show off
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
Verb
  • There’s been a lot of talk about carrying on her work, especially during these times when people feel like some of it has been eroded.
    — Helen Carefoot, Flow Space, 7 Oct. 2026
  • This hotel carries on the best of Edinburgh traditions while going above and beyond with 21st-century comforts.
    — Condé Nast, Condé Nast Traveler, 6 Oct. 2026
Definition of carry on

Browse Nearby Words

actuators
act up
acuity
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Cite this Entry

“Act up.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/act%20up. Accessed 12 Oct. 2026.

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