子弹 zǐdàn HSK5 bullet Origin Definitions Defs Strokes Stroke Words Sentences Sents 原子弹 yuánzǐdàn atomic bomb atomic bomb; A-bomb中子弹 zhōngzǐdàn neutron bomb 内爆法原子弹 nèibàofǎyuánzǐdàn implosion atomic bomb 子弹火车 zǐdànhuǒchē bullet train a high-speed passenger train, especially the Japanese Shinkansen