(mathematics) An orthogonal function whose inner product with itself is unity

(mathematics) An ordinary trigonometric function

(algebra, logic, computing) Any function based on the operations AND, OR and NOT, and whose elements are from the domain of Boolean algebra

(mathematics) homogeneous polynomial

(mathematics) The branch of mathematics dealing with infinite-dimensional vector spaces, whose elements are actually functions, as well as generalizations such as Banach spaces and Hilbert spaces.

(mathematics) Alternative spelling of homogeneous function

(mathematical analysis) Any smooth (infinitely differentiable) function f, defined on an open set D⊆ℂ( textit or⊆ℝ), whose value in some neighbourhood of any given point x_0∈D is given by the Taylor series ∑ₙ₌₀ ᪲(f⁽ⁿ⁾(x_0))/(n!)(x-x_0)ⁿ.

(mathematics) A transformation of the complex plane associated with fluid flow / (physics) The equation used to express Helmholtz free energy

(mathematics) Any function (polynomial) whose greatest exponent is 3.

A condition or capability that a system, person or object has to satisfy, fulfill or comply with. / (computing) Any of the functions of a software system, described formally.