(computing) Any character used to specify a function of a piece of software or hardware (such as carriage return of a printer)

(mathematics) Any function of a real variable whose value decreases (or is constant) as the variable increases.

(physics) The function governing the rate at which mechanical energy is converted to heat during viscous flow.

(mathematics) Any function in which an independent variable appears in the form of a logarithm; they are the inverse functions of exponential functions

(mathematics) Any function that is composed of algebraic functions, trigonometric functions, exponential functions and/or logarithmic functions, combined using addition, subtraction, multiplication and/or division

(computing) Any of a set of keys on a personal computer or terminal keyboard used to activate a predefined or programmable function.

An electronic device used to generate a signal representing the periodic value of a given mathematical function, especially sine, square, triangle and sawtooth waveforms

(mathematics) Any function whose value may be directly calculated from the independent variable.

(physics) The relationship between the energy of an electron and its ability to excite an atom to a particular excited state

An electronic analog computing device that accepts as input two periodic functions and outputs their mathematical product