functional

adj. having a purpose; useful, practical; working, functioning

Generally, functional refers to something able to fulfill its purpose or function.Functional form and functionalism (architecture) apply to architectural design.Functional (mathematics) is a term applied to functions in mathematics, computer science, and Lagrangian mechanics. Functional (ontology) refers to a property or relation in an ontology that can only hold a single value for a given individual.Functional programming is used in computer science as well. Functional symptom is sometimes used in medicine to describe symptoms that have no current visible organic basis, e.g. if they are a result of psychological or perceptual dysfunction. Historically, functional symptoms tend to be reclassified as organic as investigative techniques improve.Diatonic functionality describes a music term.
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Adjective
1. designed for or capable of a particular function or use; "a style of writing in which every word is functional"; "functional architecture"
(antonym) nonfunctional
(similar) structural
(see-also) serviceable
(attribute) function, purpose, role, use
2. involving or affecting function rather than physiology; "functional deafness"
(antonym) organic
(classification) pathology
3. relating to or based on function especially as opposed to structure; "the problem now is not a constitutional one; it is a functional one"; "delegates elected on a functional rather than a geographical basis"
(pertainym) function, purpose, role, use
4. fit or ready for use or service; "the toaster was still functional even after being dropped"; "the lawnmower is a bit rusty but still usable"; "an operational aircraft"; "the dishwasher is now in working order"
(synonym) usable, useable, in working order(p), operable, operational
(similar) serviceable
5. designed for or adapted to a function or use; "functional education selects knowledge that is concrete and usable rather than abstract and theoretical"; "functional architecture"
(similar) practical
6. (of e.g. a machine) performing or capable of performing; "in running (or working) order"; "a functional set of brakes"
(synonym) running(a), operative, working(a)
(similar) functioning

(a.)
Pertaining to, or connected with, a function or duty; official.
  

(a.)
Pertaining to the function of an organ or part, or to the functions in general.
  

1. Working correctly.
2. Pertaining to functional programming.
3. higher-order function.

<language> A program employing the functional programming approach or written in a functional language.
(1995-11-07)