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
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
Koutouvides transitioned to life after football, found success in real estate development throughout Connecticut, but the pain of losing the Super Bowl twinges and acts up like an old joint injury.
—
Dom Amore,
Hartford Courant,
8 Feb. 2026
See All Example Sentences for act up
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
Koutouvides transitioned to life after football, found success in real estate development throughout Connecticut, but the pain of losing the Super Bowl twinges and acts up like an old joint injury.
—
Dom Amore,
Hartford Courant,
8 Feb. 2026
See All Example Sentences for act up
Recent Examples of Synonyms for act up
Verb
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Being faced with an unavoidable conflict or having to work versus connecting (think staying in to do chores or homework versus spending time with friends) is the fast-track to acting out.
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The statement accused Blake of acting out of retaliation for an incident that occurred earlier in the lacrosse season.
Verb
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Its asymmetrical riff on the classic bucket hat takes the usual cut up a notch.
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The new non-stop flights will cut up to four hours off travel time compared to current one-stop services.
Verb
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In addition, referees were instructed to apply the rules regarding fouls and misconducts more strictly – a move meant to protect players and their inventiveness.
Verb
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On Monday, OpenAI will host its first-ever Cannes Lions event a few blocks away from the Palais where the awards are given, along the boulevard where the major tech players and ad holding companies have traditionally set up shop to show off to clients.
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The actress showed off micro bangs and a chin-grazing chop for her role as a manager.
Verb
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Santana-Mateo was booked on charges of breach of peace, engaging police in a pursuit, disobeying the direction of officer, reckless driving, failure to obey a stop sign, failure to drive right, failure to obey a traffic control signal and driving the wrong way on a one way.
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In 2024, the agency claimed that X security staff sometimes had to pointedly disobey Musk in order to remain in compliance.
Verb
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Ortiz navigated past 17 other horses around the final turn and made a hard charge down the stretch.
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Ortiz navigated past 17 other horses around the final turn and made a hard charge down the stretch.
Verb
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The brief clip showed off a new cast of characters, beginning with fuzzy television static before exploding into a montage propelled by intense music and kinetic bursts of action, carrying on the spirit of the first season through energetic animation and heavily stylised art.
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While Starmer wants to carry on with business as usual, he’s not allowed to make new major policy announcements or spending commitments during what remains of his time in office.
Cite this Entry
“Act up.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/act%20up. Accessed 25 Jun. 2026.
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