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
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Recent Examples of act up
Johnson, who struggles with a neuroma, swears by her Oofos mules to keep it from acting up.
—
Jennifer Heimlich, SELF, 29 Aug. 2025
Millennials are all about heading to the doctor’s office when their guts start acting up—and both experts agreed that’s a positive thing.
—Alisa Hrustic, Health, 29 July 2025
But if King’s shoulder acts up again, the Padres will enter October shorthanded.
—The Athletic Mlb Staff, New York Times, 29 July 2025
Just in time for the big opening, Charlotte’s vertigo starts acting up.
—Maggie Fremont, Vulture, 18 July 2025
See All Example Sentences for act up
Jennifer Heimlich, SELF, 29 Aug. 2025
Millennials are all about heading to the doctor’s office when their guts start acting up—and both experts agreed that’s a positive thing.
—Alisa Hrustic, Health, 29 July 2025
But if King’s shoulder acts up again, the Padres will enter October shorthanded.
—The Athletic Mlb Staff, New York Times, 29 July 2025
Just in time for the big opening, Charlotte’s vertigo starts acting up.
—Maggie Fremont, Vulture, 18 July 2025
See All Example Sentences for act up
Recent Examples of Synonyms for act up
Verb
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Then Bostwick hits the road through November for screenings around the country with live shadow casts of performers acting out the movie in front of the screen.—
Brian Truitt,
USA Today,
25 Sep. 2025
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James acts out by angrily finishing the painting of a sign on the Guinness plant wall.—
Keith Phipps,
Vulture,
25 Sep. 2025
Verb
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To mulch leaves, use a lawn mower or leaf shredder to cut up your leaves into small pieces and then pile them up around your plants.—
Maia Pandey,
jsonline.com,
25 Sep. 2025
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Investigators allegedly recovered evidence from Louisma's car, including a pocketknife with blood stains on it, machetes, a rope, a roll of duct tape, pink HeyDude shoes, and a cut up pink shirt with duct tape wrapped around it, CBS2 Iowa reports.—
KC Baker,
PEOPLE,
24 Sep. 2025
Verb
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Decorators, manufacturers, magazines, department stores, artists and foreign governments flocked to Paris to show off their latest creations, drawing more than 16 million visitors.—
Joelle Diderich,
Footwear News,
25 Sep. 2025
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Beethoven's Ninth, Milwaukee Symphony Orchestra Outgoing Milwaukee Symphony Music Director Ken-David Masur has packed his concluding season here with major choral works to show off the Milwaukee Symphony Chorus in its 50th year.—
Jim Higgins,
jsonline.com,
25 Sep. 2025
Verb
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Running or horsing around with sparklers can also cause injuries and burns when users trip and fall.—
Justin Laube,
EverydayHealth.com,
2 July 2025
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Heath Ryan, who represented Australia in dressage at the 2008 Olympics, can be seen in the video – which the rider said is about two years old – hitting a horse around 40 times.—
Matias Grez,
CNN Money,
13 June 2025
Verb
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The next day, Alex begs Mia to put her on TMS to talk about the deep fake, but Mia won’t, because that would be directly disobeying Stella and Celine’s order for Alex to keep quiet.—
Kimberly Roots,
TVLine,
24 Sep. 2025
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Hamas has called on residents of Gaza City to disobey the evacuation order.—
Brady Knox,
The Washington Examiner,
8 Sep. 2025
Verb
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In a prerecorded message, Lee said silencing a voice cannot silence an idea and urged attendees to carry on Kirk’s mission.—
Alex J. Rouhandeh,
MSNBC Newsweek,
1 Oct. 2025
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Content creator Mychal Threets, also known as Mychal the Librarian, will carry on the legacy as the new host.—
Jason P. Frank,
Vulture,
30 Sep. 2025
Verb
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By the early post-World War II period, the demographic cohort most likely to rebel against authority—namely, youth—had been molded by Soviet institutions in which the revolutionary teachings of Marxism-Leninism had achieved the status of sacred canon.—
Benjamin Nathans
September 24,
Literary Hub,
24 Sep. 2025
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Set after the Norman invasion of England, Rob (Patten) witnesses the execution of his father, a Saxon forester, which incites him to rebel.—
Nick Romano,
Entertainment Weekly,
22 Sep. 2025
Cite this Entry
“Act up.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/act%20up. Accessed 2 Oct. 2025.
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