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
Then the engine started acting up, which would have cost up to $10,000 to fix.
—
Shannon Pettypiece, NBC news, 22 Sep. 2025
Lots of time spent acting up and acting out with your family.
—Outside Online, 3 Sep. 2025
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
See All Example Sentences for act up
Shannon Pettypiece, NBC news, 22 Sep. 2025
Lots of time spent acting up and acting out with your family.
—Outside Online, 3 Sep. 2025
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
See All Example Sentences for act up
Recent Examples of Synonyms for act up
Verb
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Family described Wilks as an only son who was acting out of his character, which is normally soft-spoken and well-mannered.—
David Clarey,
jsonline.com,
10 Oct. 2025
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Day-Lewis often acted out dialogue, as speed typist Ronan took everything down on the computer.—
Anne Thompson,
IndieWire,
9 Oct. 2025
Verb
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The boat therefore needed metal or plastic cages installed around the engines, so that the diver wouldn’t get accidentally cut up by their blades — and finding a boat and then the right cages fit onto the boat would take time.—
Samanth Subramanian,
The Dial,
14 Oct. 2025
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Techniques like this have been around for some time, but Micro-C uses an enzyme that can cut up DNA more finely than before.—
Quanta Magazine,
Quanta Magazine,
8 Oct. 2025
Verb
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That journey resulted in plenty of dishes that show off the bold flavors of the region.—
Nicole Hoey,
Robb Report,
16 Oct. 2025
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Bar Italia are definitely not shy about showing off their moody rock influences — a little Slowdive, a lot of the Cure, plenty of the Velvets and Spacemen 3 and Sonic Youth.—
Rob Sheffield,
Rolling Stone,
16 Oct. 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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In Missouri, disobeying traffic lights is considered a moving violation.—
Eleanor Nash,
Kansas City Star,
15 Oct. 2025
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This was neither the first nor the last time that Patton disobeyed an order.—
Davis Winkie,
USA Today,
14 Oct. 2025
Verb
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Without receivers CeeDee Lamb and KaVontae Turpin, Prescott got multiple receivers involved as the game carried on.—
Nick Harris,
Fort Worth Star-Telegram,
13 Oct. 2025
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Kelsea Ballerini carried on her legacy of blending pop and country while staying true to the storytelling roots of Nashville on Patterns.—
Tomás Mier,
Rolling Stone,
13 Oct. 2025
Verb
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Otherwise, the only alternative is rebelling against the government.—
Big Think,
Big Think,
10 Oct. 2025
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Still, Johnson can try to block the discharge effort in the Rules Committee, though the panel has rebelled against him in the past.—
Chad de Guzman,
Time,
7 Oct. 2025
Cite this Entry
“Act up.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/act%20up. Accessed 18 Oct. 2025.
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