to make a mistake; to make an error (i.e. in calculation) / to confuse, to mistake something for something else

to misrecognize; to read something wrong, etc.

演算子: (mathematics, computing) operator

演算: to calculate

演算: operation

演算機: processor / 演算器: functional unit (e.g. in analog computing)

the result, effect, consequence / the performance, the accomplishment, the achievement

(rare) bear fruit

(mathematics, computing) A function or other mapping that carries variables defined on a domain into another variable; operator.

to calculate