spitball noun 2verb 2forms 3 noun2 •A balled-up piece of paper, moistened with saliva (by chewing) and shot through a drinking straw. •A pitch of a baseball that has been partly covered with saliva, illegal at most levels. verb2 •To moisten the ball with saliva before pitching it. •(figurative) To brainstorm ideas.Maybe, and I'm just spitballing here, maybe, we have a responsibility as officers to train Santiago. — 1992 formsspitballed · spitballing · spitballs