spit·ball 
/ˈspɪtˌbɑ:l/ noun
plural spit·balls /ˈspɪtˌbɑ:l/ noun [count] US 1 : a small piece of paper that is chewed and rolled into a ball so that it can be thrown or shot at someone
▪ The kids were shooting spitballs at each other. 2 baseball : an illegal pitch in which the ball is made wet with saliva or sweat
▪ The kids were shooting spitballs at each other.
