(n.) One whose business is to make sport for others; a buffoon; a zany; especially, one who attends a mountebank or quack doctor.

Columbine Hanswurst Harlequin Pantalone Pantaloon Polichinelle Pulcinella Punch Punchinello Scaramouch ass bad boy booger born fool buffo bugger clown cutup devil doodle egregious ass elf enfant terrible figure of fun fool funmaker harlequin hood hoodlum hooligan ignoramus imp jack-pudding jackass jester joker jokester knave little devil little monkey little rascal lunatic merry-andrew milksop minx mischief mischief-maker mooncalf motley motley fool perfect fool pickle-herring pixie practical joker prankster puck rapscallion rascal rogue rowdy ruffian scamp scapegrace schmuck softhead sop stupid ass tomfool wag zany