an object, such as a bullet, that is fired from a gun or other weapon 射弹（如子弹、炮弹等） any object that is thrown as a weapon （作为武器的）发射物；导弹
Word Originmid 17th cent.: modern Latin, from project- ‘thrown forth’, from the verb proicere ‘throw forth’, from pro- ‘forth’ + jacere ‘to throw’.