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 The black flies are not the only troublesome creature acting up during the unseasonably warm weather. — Clara Harter, Los Angeles Times, 28 Mar. 2026 Bruce, as the stunt shark built to menace them is nicknamed, is acting up and delaying the acting itself. — Christopher Smith, Oc Register, 10 Mar. 2026 Meanwhile, the guests, who have literally just arrived five minutes ago, are already acting up. — Rafaela Bassili, Vulture, 10 Mar. 2026 Excess dust may also cause your allergies to act up. — Madeline Buiano, Martha Stewart, 22 Feb. 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
  • The next time your child acts out, try doing these five things.
    — Juli Fraga, CNBC, 6 Sep. 2026
  • Inside, under flickering lights, a group of reluctant strangers is coaxed into acting out, in a converted gymnasium, a wild tale promising redemption from agonizing tragedy.
    — Theater Critic, Los Angeles Times, 5 Sep. 2026
Definition of act out
Verb
  • The Arab coins, known as dirhams, are cut up and have similar inscriptions to those found in silver hoards from the 9th century, Nordjyske Museer said.
    — Amarachi Orie, CNN Money, 4 Sep. 2026
  • What parents can do on hectic mornings Nemours recommends doing as much as possible the night before, from setting out dishes to cutting up fruit.
    — Ashley Lynch, Fort Worth Star-Telegram, 25 Aug. 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
  • Kienholz showed off his mobility both as a runner and passer, effectively threw to all levels of the field and made clutch play after clutch play in the second half.
    — Antonio Morales, New York Times, 7 Sep. 2026
  • The bush is deciduous but shows off gold, orange, and red fall color.
    — Mary Marlowe Leverette, The Spruce, 6 Sep. 2026
Definition of show off
Verb
  • 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
  • The violations are disobeying orders and conduct unbecoming an officer.
    — Charlie D'Agata, CBS News, 25 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
  • Part of the frustration and fascination of these climbing docs is that the filmmakers can never quite answer the question of why these people — tenacious, but undoubtedly masochistic — carry on and up the mountain again and again.
    — Ryan Lattanzio, IndieWire, 3 Sep. 2026
  • Later that night, there’s more fallout from recent events — albeit of a more therapeutic kind — when Keeley and Rebecca share their problems while watching Bridesmaids before ending the night determined to carry on.
    — Keith Phipps, Vulture, 2 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 10 Sep. 2026.

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