Definition of act up
- the children were acting up
- this typewriter is acting up again
- her rheumatism started to act up
the two-year-old was acting up in church so much that her dad had to take her outside
you should have seen the boys acting up when they put on their aprons
What made you want to look up act up? Please tell us where you read or heard it (including the quote, if possible).
of yeast or being unsettled or frivolous
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