1 simpleton, ninny, ninny-hammer, nincompoop, ass, jackass, dunce, dolt, halfwit, numskull or numbskull, blockhead, bonehead, pinhead, silly, feather-brain, loon, goose, booby, jay, goon, mooncalf, idiot, ignoramus, dim-wit, nitwit, halfwit, imbecile, moron, clod, clodpole, clodpoll, clodpate, oaf, Psychology retardate, Scots gomerel, Colloq birdbrain, dumb-bell, fat-head, chump, twit, knuckle-head, chucklehead, nit, twerp or twirp, Brit pillock, US and Canadian jerk, retard; Slang sap, dope, Brit git, Australian boofhead:
He's such a fool he'll believe anything.
2 (court) jester, clown, comic, comedian or comedienne, entertainer, zany, buffoon, merry andrew, farceur, joker, jokester, droll, Punch, Punchinello, pierrot, harlequin:
In Shakespeare's plays, the fool is often the wisest character.
3 butt, dupe, gull, victim, cat's-paw, Colloq chump, greenhorn, (easy) mark, US fall guy; Slang pigeon, sucker, stooge, Brit mug:
His co-workers liked to make a fool out of him.
4 trick, deceive, take in, swindle, defraud, hoax, cheat, fleece, cozen, hoodwink, bluff, dupe, gull, humbug, delude, mislead, make a fool of; pull the wool over (someone's) eyes, have (someone) on, pull (someone's) leg, tease, twit, Archaic chouse; Colloq kid, con, snow, do a snow job on, bamboozle, put one or something over on, pull something or a fast one on, Brit twist, Chiefly US and Canadian josh; Slang pluck, Brit nobble:
When he said the diamond was fake, he certainly fooled me. I think she was fooling when she said she'd inherited millions.
5 joke, jest, banter, tease, twit, feign, fake, pretend, make believe, Colloq kid:
She insists that she is not fooling but dead serious.
6 fool with or around or about (with). play (around or about) (with), toy or trifle (with), mess or fiddle (around or about) (with), monkey (around or about) with, meddle (with), tamper with, fribble (with):
Please stop fooling with the dials on the radio.
7 fool around or about.
(a) play or mess around or about, gambol, frolic, romp, cavort:
Stop fooling around and get serious.
(b) waste or fritter away or squander or kill time, fribble, loiter, dawdle, idle, Brit potter (about), lark or muck about or around, US putter around or about, Colloq footle:
She's always fooling around instead of getting on with her work.