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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
  • Jo, raised by her grandmother, is hyperactive, wild, free-spirited, and a talented artist but often acts out in school.
    — Parents, Parents, 25 Sep. 2026
  • Those include the harrowing night terrors Tony begins to experience — intense, frightening nightmares that cause people with Parkinson’s to violently act out in their sleep.
    — Michael Rechtshaffen, HollywoodReporter, 16 Sep. 2026
Definition of act out
Verb
  • Duke Energy crews are working to cut up the tree and replace the pole, officials said.
    — Mark Price, Charlotte Observer, 15 Sep. 2026
  • Later, it was prevented from being cut up to decorate a carnival float.
    — Lauren Frayer, NPR, 9 Sep. 2026
Definition of cut up
Verb
  • 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
  • Mark Zuckerberg showed off Meta’s new glasses, named Meta VR Glasses, at the company’s annual Connect event in Menlo Park, Calif.
    — Sebastian Herrera, Fortune, 24 Sep. 2026
  • One of Zuckerberg’s live demos of the night also showed off the glasses’ ability to use hologram technology to project a photorealistic digital version of a person, including their real-time expressions and reactions, for hands-free video calling.
    — Kaitlyn Huamani, Chicago Tribune, 24 Sep. 2026
Definition of show off
Verb
  • 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
  • Jeanie Buss also wants proof that Joey and Janie Buss disobeyed the 2017 court order, along with an order requiring them to show cause of why they should not be held in contempt of court.
    — Michael McCann, Sportico.com, 28 Aug. 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
  • In the tangled greenery of a Ugandan national park, mountain gorillas sit among the leaves, calmly carrying on as tourists trek into their forest home.
    — ABC News, ABC News, 24 Sep. 2026
  • Still, Sheeran carried on with his tour over the weekend, addressing the controversy and expressing a middling stance on Israel’s war in Gaza.
    — Alexandra Del Rosario, Los Angeles Times, 24 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 30 Sep. 2026.

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