verb

• (intransitive) To change the direction of motion after hitting an obstacle.
  "The tennis ball bounced off the wall before coming to rest in the ditch."
• (intransitive) To move quickly up and then down (or vice versa), once or repeatedly.
  "He bounces nervously on his chair."
• (transitive) To cause to move quickly up and down, or back and forth, once or repeatedly.
  "He bounced the child on his knee."
• (transitive, colloquial) To suggest or introduce (an idea, etc.) to (off or by) someone, in order to gain feedback.
  "I'm meeting Bob later to bounce some ideas off him about the new product range."

noun

• (Internet) An email that returns to the sender because of a delivery failure.
• (quantum mechanics) A hypothetical event where a collapsing system, such as a universe in the Big Bounce theory, reaches a point of extreme density and then rebounds back into an expanding phase, essentially reversing the contraction due to quantum mechanical effects.
• (slang) The sack, dismissal.
  "Someone more clever than I said, "It's not the bounce that counts, it's the bounce back. ""
• (archaic) A bang, boom.
  "I don't value her resentment the bounce of a cracker."