Definition of "functional" in English

adjective

1. In good working order.

2. Useful; serving a purpose, fulfilling a function.

   • That sculpture is not merely artistic, but also functional: it can be used as a hatrack.

3. Only for functional purposes, notably in architecture.

   • A functional construction element generally must meet higher technical but lower aesthetical requirements.

4. Of or relating to one's role or office; official.

   • functional responsibilities

5. (physiology, psychology) Characterizing functioning in environment, being symptoms that do not presuppose alteration of organic structure.

6. Optimized for all-around physiological benefit.

   • functional coffee
   • functional fitness

7. (mathematics) Of or relating to a function or functions.

8. (computing theory) Having semantics defined purely in terms of mathematical functions, without side-effects.

noun

1. (mathematics) A function that takes a function as its argument; more precisely, a function whose argument varies in a space of (real or complex valued) functions and whose value belongs to a monodimensional space.

   • An example of a functional is the definite integration of integrable real functions in a real interval.

2. (mathematics, functional analysis) A scalar-valued linear function on a vector space.

3. (computing) An object encapsulating a function pointer (or equivalent).