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
  • She was thrown right into the mix, acting out a meet-cute with Montana Jordan’s Georgie Cooper that culminated with a kiss.
    — Ryan Coleman, Entertainment Weekly, 26 Oct. 2026
  • With the final credits barely up, Musk is acting out exactly that blueprint.
    — Steven Zeitchik, HollywoodReporter, 22 Oct. 2026
Definition of act out
Verb
  • After Szabo cuts up Matt’s face in one of many graphic scenes, the actor loses his career and just about everything else in his life.
    — Glenn Garner, Deadline, 21 Oct. 2026
  • Union President Carrie Kyung said the plan includes cutting up to 18 English learner teachers and would affect at least two dozen schools.
    — Jason Rantala, CBS News, 20 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
  • Why dupe culture hits different for Gen Z Pulling off a convincing dupe is a way to show off shopping intel and personal taste without the designer price tag attached.
    — Ashley Lynch, Fort Worth Star-Telegram, 23 Oct. 2026
  • Mi Cariño, built as a love letter to Latin cuisine, is centered on elevated Mexican flavors, showing off bright and smoky elements with a West Coast influence.
    — Heidi Finley, Charlotte Observer, 22 Oct. 2026
Definition of show off
Verb
  • The league fails to react to any of the players who disobey the rules.
    — Joe Kinsey OutKick, FOXNews.com, 20 Oct. 2026
  • Smith was charged with disobeying an officer, a misdemeanor, according to Placer Superior Court records.
    — Theresa Clift, Sacbee.com, 19 Oct. 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
  • As the fund’s general partner, the NFL will collect some management fees and carry on the investments, a consistent and bankable income stream that is not shared with players as part of the salary cap.
    — Scott Soshnick, Sportico.com, 22 Oct. 2026
  • In Hargeisa, meanwhile, the country that doesn’t exist carries on.
    — Mahbub Abdillahi, Christian Science Monitor, 22 Oct. 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 27 Oct. 2026.

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