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
  • Rifkin also open a bag containing Machado’s black bra and purple T-shirt, both of which were cut up by scissors.
    — Grethel Aguila, Miami Herald, 1 Oct. 2026
  • Duke Energy crews are working to cut up the tree and replace the pole, officials said.
    — Mark Price, Charlotte Observer, 15 Sep. 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
  • But showing off or gussying things up is the last thing on Anderson’s mind; high concepts aren’t listed on the program.
    — David Fear, Rolling Stone, 2 Oct. 2026
  • Football season is officially underway, and showing off your team spirit can go way beyond throwing on a jersey.
    — Casey DelBasso, ABC News, 2 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
  • Other fabric scraps of the original dress were used to create handkerchiefs for Noah, her brothers, and herself to carry on the day.
    — Shelby Wax, Vogue, 2 Oct. 2026
  • But a new wave of indignation swept Spain when Abascal, who uses a wheelchair, was carried on a stretcher from her apartment after police cordoned off the street.
    — ABC News, ABC News, 30 Sep. 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 9 Oct. 2026.

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