act up

phrasal verb·1 sense·particle up

Usefulness

Meanings

1

Behave badly or stop working properly

Why “up”? Something normal is disturbed. Feelings, systems, machines, or behavior become noisy, troubled, or out of control.

My laptop is acting up again.
My laptop is not working properly again.
The children acted up during dinner.
The children behaved badly during dinner.

Don't confuse with

act upact out

Act up means behave badly or stop working properly. Act out means express feelings through aggressive or attention-seeking behaviour.

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My laptop is acting up again. What does it mean?

Nearby in the meaning map

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