(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.

(physiology) A normal physical process that occurs in the body. / (euphemistic) An excretory function of an organism, usually the discharging of feces and urine.

(computing, database normalization) A constraint between two sets of attributes in a relation.

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.

plural of functional requirement

A real-valued function on a differentiable manifold such that, at each point in its domain where the function's differential is zero, the function's Hessian is nonsingular.

(biology) Any function of the body that is essential for maintaining life, especially breathing and circulation.

(mathematics) A function whose range is a subset of the set of real numbers.

(mathematics) A function whose range is a subset of the set of complex numbers.