(computer science) A mathematical function that can be computed using an abstract computation machine such as Turing machine.

(mathematics) A unary function that preserves the addition operation; a unary function f such that for any x and y: f(x + y) = f(x) + f(y).

plural of function key

(medicine) The remaining capacity of an organ or body part to fulfil its physiological activity; (especially) in the context of disease, ageing, or impairment.

(logic) A function which assigns a truth value to every well-formed formula, which is identical to the model's interpretation function when applied to atomic propositions, and which otherwise assigns a truth value recursively depending on the formula's top logical connective and the truth values of the subformulae surrounding that logical connective.

(mathematics) The function that determines the sign of a real number, yielding -1 if negative, +1 if positive, or otherwise zero.

(mathematics) Any function of a polynomial whose greatest exponent is 5.

(linguistics) A word that has little meaning when standing alone, but instead serves to express grammatical relationships with other words within a sentence, or specify the attitude or mood of the speaker, such as prepositions, pronouns, auxiliary verbs, or conjunctions.

plural of function object

(object-oriented programming) An object that encapsulates a function pointer (or equivalent).