A popular and funny person who grabs attention by craking a joke or lightly teasing others. Often has a dry sense of humor (says something funny with a straight face as though it were not funny) and usually uses sarcasm. Nickname for one might be "CJ."
Literally, the entertainer of the King.
Jimmy: "I don't understand this book!"
Tommy: "Maybe you should read it..."
Jimmy: "Thanks, court jester."