A jester was a historical entertainer either employed to entertain a ruler or other nobility in medieval or Tudor times or was an itinerant performer who entertained common folk at fairs and markets. a professional joker or “fool” at a medieval court, typically wearing a cap with bells on it and carrying a mock scepter. synonyms: fool, court fool, court jester, clown, harlequin, pantaloon; More a person who habitually plays the fool. synonyms: joker, clown, comedian, comic, humorist, wag, wit, prankster, jokester, trickster, buffoon; More