'Ping-pong ball' definitions:

Definition of 'ping-pong ball'

(from WordNet)
noun
Light hollow ball used in playing table tennis

Definition of 'Ping-pong ball'

From: GCIDE
  • Ping-pong ball \Ping"-pong ball`\, v. i. the small hollow celluloid ball used for the game of ping-pong. [PJC]