Origin: Latin prefix pre-
Definition, synonyms and related words
For a given function, the set of all elements of the domain that are mapped into a given subset of the codomain; (formally) given a function ƒ : X → Y and a subset B ⊆ Y, the set ƒ^(−1)(B) = {x ∈ X : ƒ(x) ∈ B}.