Functional1. (a.) Pertaining to, or connected with, a function or duty; official.
2. (a.) Pertaining to the function of an organ or part, or to the functions in general.
Thesaurus Entries
acting, active, adjectival, advantageous, adverbial, agential, agentival, agentive, appropriate, at work, attributive, banausic, behavioral, beneficial, commodious, conjunctive, copulative, correct, effective, effectual, efficacious, efficient, employable, essential, expedient, fitting, formal, functioning, glossematic, go, going, going on, good for, grammatic, handy, helpful, important, in exercise, in force, in hand, in operation, in play, in practice, in process, in the works, inaction, industrial, intransitive, linking, managerial, manipulational, neuropsychiatric, nominal, of general utility, of help, of service, of use, official, on foot, on the fire, ongoing, operating, operational, operative, participial, performing, postpositional, practicable, practical, practicing, pragmatical, prepositional, pro, professional, pronominal, proper, psychiatric, psychobiological, psychodynamic, psychogenic, psychological, psychoneurological, psychopathic, psychopathological, psychophysical, psychophysiological, psychosexual, psychosocial, psychosomatic, psychotic, running, serviceable, serving, structural, substantive, syntactic, tagmemic, technical, transitive, useful, utilitarian, verbal, vocational, working