paper pellet; spitball
A small wad of paper, often chewed or folded, used as a projectile. The term is neutral but may evoke schoolyard mischief.
I got scolded by the teacher for shooting a paper pellet during class.
He blew a spitball through a straw.
Standard kanji spelling for 'paper pellet'.
Mixed kanji-kana spelling, easier to read than the full kanji form.
Compound of 紙 (kami, 'paper') and 礫 (tsubute, 'throwing stone'). The word literally means 'paper stone'.