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
  • Jenn asks Ryan if Dominic acting out at school has anything to do with her divorce.
    — Brian Moylan, Vulture, 30 Oct. 2026
  • This is vital, as sleepers might otherwise act out their dreams and harm themselves or others.
    — RJ Mackenzie, Popular Science, 29 Oct. 2026
Definition of act out
Verb
  • Californios’ reign began to vanish even before the discovery of gold, when droughts and floods wiped out their easygoing livelihoods, and their lands were cut up, sold off, and their land grants swept aside by the new state.
    — Patt Morrison, Los Angeles Times, 30 Oct. 2026
  • The board's original proposal called for cutting up to 18 English learner teachers across the district.
    — Beret Leone, CBS News, 30 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
  • They can be planted along foundations, add height and layers to flower beds, or planted as an accent to show off fall color, beautiful blooms, or other interesting features.
    — Karen Brewer Grossman, Southern Living, 6 Nov. 2026
  • His wife and frequent collaborator Bianca Censori sat front row, naturally showing off one of her husband’s latest boot designs.
    — Karla Rodriguez, Footwear News, 5 Nov. 2026
Definition of show off
Verb
  • What the museum has built, then, is a pliable, predictable, and programmable worker, one that offers all the benefits of Dalí’s celebrity and personality with none of the drawbacks of a worker who might disagree or disobey.
    — Literary Hub, Literary Hub, 30 Oct. 2026
  • One even got in trouble and is shackled to a wooden pillory, serving as an example to others who disobey the crown and engage in piracy.
    — Patrick Connolly, The Orlando Sentinel, 22 Oct. 2026
Definition of disobey
Verb
  • And lo, that’s how The Godfather wound up horsing around on a bouncy sorta-rap cut with London’s club muse and scene gadfly Normski.
    — Gabriel Szatan, Pitchfork, 2 Nov. 2026
  • Also, don’t get too out of control horsing around with friends in the water.
    — John Natale, Hartford Courant, 16 Aug. 2026
Definition of horse around
Verb
  • The good vibes carried on with the year’s most competitive bidding war, eventually won by A24.
    — Lily Ford, HollywoodReporter, 6 Nov. 2026
  • When the family moved to Georgia and bought the Tea House, Major’s daughter, Evangeline, decided to carry on the tradition.
    — Heather L. Whitley, Southern Living, 3 Nov. 2026
Definition of carry on

Browse Nearby Words

actuators
act up
acuity
See all Nearby Words

Cite this Entry

“Act up.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/act%20up. Accessed 10 Nov. 2026.

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