noun
He's such a fool he'll believe anything
In Shakespeare's plays, the fool is often the wisest character
His co-workers liked to make a fool out of him
verb
When he said the diamond was fake, he certainly fooled me. I think she was fooling when she said she'd inherited millions
She insists that she is not fooling but dead serious
Please stop fooling with the dials on the radio
fool around or about
Stop fooling around and get serious
She's always fooling around instead of getting on with her work