tummler

/ˈtʊmlər/
noun
  1. A person who entertains others, especially in a social setting, by telling jokes, performing tricks, or keeping the mood lively.
    • The resort hired a tummler to lead games and activities for the guests.
    • At the party, Uncle Joe was the tummler, making everyone laugh with his stories.
    • She acted as the tummler at the family reunion, organizing silly contests.