rubber bullet

:  one that rubs

:  an instrument or object (such as a rubber eraser) used in rubbing, polishing, scraping, or cleaning

:  something that prevents rubbing or chafing

:  a contest consisting of an odd number of games won by the side that takes a majority (such as two out of three)

:  an odd game played to determine the winner of a tie

:  a round or elongated missile (as of lead) to be fired from a firearm

:  cartridge

:  something resembling a bullet (as in curved form)