柠檬酸循环 níngméngsuānxúnhuán citric acid cycle Origin Definitions Defs Strokes Stroke Words Sentences Sents 柠檬酸 檸檬酸 níngméngsuān citric acid An organic compound occurring naturally in citrus fruits, used as a food additive and for industrial cleaning; also called 枸橼酸 jǔyuánsuān.循环 循環 xúnhuán noun cycle a circle, loop, or repeating sequence of events; circulation