gumball

noun

1. Chewing gum sold as a ball usually coated with colored hard sugar.

   “Remember those clear globe dispensers with gumballs for a penny?”

2. (slang)A silly, laughable person.

   “When he drinks too much he's a gumball.”

3. (US, slang)The flashing lights on top of a police car.
4. The spiky seedpod of the sweet gum tree.