1. phrasal verb If you fool around, you behave in a silly, dangerous, or irresponsible way. [V P] ⇒ They were fooling around on an Army firing range. [V P + with] ⇒ Have you been fooling around with something you shouldn't? 2. phrasal verb If someone fools around with another person, especially when one of them is married, they have a casual sexual relationship. [V P + with] ⇒ Never fool around with the clients' wives. [V P] ⇒ Her husband was fooling around. 3. phrasal verb → fool If you fool around, you behave in a playful, childish, and silly way, often in order to make people laugh. In British English, you can also say you fool about. [V P] ⇒ Stop fooling about, man. [V P] ⇒ They fooled around for the camera.
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