[func.tion] n [L function-, functio performance, fr. fungi to perform; prob. akin to Skt bhunkte he enjoys] (1533) 1: professional or official position: occupation
2: the action for which a person or thing is specially fitted or used or for which a thing exists: purpose
3: any of a group of related actions contributing to a larger action; esp: the normal and specific contribution of a bodily part to the economy of a living organism
4: an official or formal ceremony or social gathering
5. a: a mathematical correspondence that assigns exactly one element of one set to each element of the same or another set b: a variable (as a quality, trait, or measurement) that depends on and varies with another "height is a ~ of age"; also: result "illnesses that are a ~ of stress"
6: characteristic behavior of a chemical compound due to a particular reactive unit; also: functional group 7: a computer subroutine; specif: one that performs a calculation with variables provided by a program and supplies the program with a single result -- func.tion.less adj syn function, office, duty, province mean the acts or operations expected of a person or thing. function implies a definite end or purpose that the one in question serves or a particular kind of work it is intended to perform "the function of language is two-fold: to communicate emotion and to give information --Aldous Huxley". office is typically applied to the function or service expected of a person by reason of his trade or profession or his special relationship to others "they exercise the offices of the judge, the priest, the counsellor --W. E. Gladstone". duty applies to a task or responsibility imposed by one's occupation, rank, status, or calling "it is the judicial duty of the court, to examine the whole case --R. B. Taney". province applies to a function, office, or duty that naturally or logically falls to one "nursing does not belong to a man; it is not his province --Jane Austen".
[2]function vi func.tioned ; func.tion.ing (1856) 1: to have a function: serve "an attributive noun ~s as an adjective"
2: to carry on a function or be in action: operate "a government ~s through numerous divisions"