ACT UP Synonyms: 58 Similar and Opposite Words

act up

verb

Definition of act up next

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

Relevance

Antonyms & Near Antonyms

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

Recent Examples of Synonyms for act up

Verb

Created by Eugene Pack and co-created by Dayle Reyfel, Celebrity Autobiography features stars reading — and dramatically acting out — excerpts from famous memoirs, leaning into the unintentionally funny, overly revealing and often absurd moments found within their pages.

— Dave Quinn, PEOPLE, 9 May 2026
But Rushing didn’t act out, McDonnell said.

— Fabian Ardaya, New York Times, 8 May 2026