mathematical function

quantity dependent on other quantities for its value (Mathematics)

The mathematical concept of a function expresses dependence between two quantities, one of which is given (the  independent variable, argument of the function, or its "input") and the other produced (the dependent variable, value of the function, or "output"). A function associates a unique output with every input element drawn from a fixed set, such as the real numbers.
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Noun
1. a mathematical relation such that each element of one set is associated with at least one element of another set
(synonym) function
(hypernym) mathematical relation
(hyponym) inverse function
(classification) mathematics, math, maths