[equa.tion] n (14c) 1 a: the act or process of equating b (1): an element affecting a process: factor (2): a complex of variable factors c: a state of being equated; specif: a state of close association or identification "bring governmental enterprises and payment for them into immediate ~ --R. G. Tugwell"
2. a: a usu. formal statement of the equality or equivalence of mathematical or logical expressions b: an expression representing a chemical reaction quantitatively by means of chemical symbols