act up

phrasal verb·1 sense·particle up

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 behaving badly again.
The printer acted up during checkout.
The printer stopped working properly during checkout.

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?

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