Read Edit View history 二阶 èrjiē second-order Origin Definitions Defs Strokes Stroke Words Sentences Sents created sense approved 二阶/二階 · èrjiē · second-order 2026/03/04 二阶 / 二階 èrjiē second-order second order or quadratic (referring to the degree or order in mathematics) 这个二阶微分方程很难解。 created sense Mar 4, 2026, 02:25 AM