一經 Simplified: 一经 On the HSK 7-9 vocabulary list, at CEFR level C2. yījīng ㄧ ㄐㄧㄥ as soon as once (an action has been completed) Sources CC-CEDICT, CC BY-SA 4.0 pinyinjs, Apache-2.0 国际中文教育中文水平等级标准, 中华人民共和国教育部, MIT