equation
/ɪˈkweɪʃən/noun
1
- Mathematics a statement that the values of two mathematical expressions are equal (indicated by the sign =)【数】等式, 方程（式）。
2
- mass noun the process of equating one thing with another等同; 相等; 平衡：
the equation of science with objectivity.
对科学性和客观现实的等量齐观。
2.1
the equation
a situation or problem in which several factors must be taken into account（必须考虑多种因素的）复杂局面（或问题）, 综合体, 复合体：money also came into the equation.
钱也成了必须考虑的因素之一。
3
- Chemistry a symbolic representation of the changes which occur in a chemical reaction, expressed in terms of the formulae of the molecules or other species involved【化】反应式, 化学方程式。
短语
equation of the first （或 second等） order
- Mathematics an equation involving only the first derivative, second derivative, etc.【数】一次（或二次等）方程。
词源
late Middle English: from Latin aequatio （n -）, from aequare 'make equal' （see EQUATE）.