/fungk"sheuhn/ , n.
1. the kind of action or activity proper to a person, thing, or institution; the purpose for which something is designed or exists; role.
2. any ceremonious public or social gathering or occasion.
3. a factor related to or dependent upon other factors: Price is a function of supply and demand.
4. Math.
a. Also called correspondence, map, mapping, transformation . a relation between two sets in which one element of the second set is assigned to each element of the first set, as the expression y = x 2 ; operator.
b. Also called multiple-value function . a relation between two sets in which two or more elements of the second set are assigned to each element of the first set, as y 2 = x 2 , which assigns to every x the two values y = + x and y = - x.
c. a set of ordered pairs in which none of the first elements of the pairs appears twice.
5. Geom.
a. a formula expressing a relation between the angles of a triangle and its sides, as sine or cosine.
b. See hyperbolic function .
6. Gram.
a. the grammatical role a linguistic form has or the position it occupies in a particular construction.
b. the grammatical roles or the positions of a linguistic form or form class collectively.
7. Sociol. the contribution made by a sociocultural phenomenon to an ongoing social system.
v.i.
8. to perform a specified action or activity; work; operate: The computer isn't functioning now. He rarely functions before noon.
9. to have or exercise a function; serve: In earlier English the present tense often functioned as a future. This orange crate can function as a chair.
[ 1525-35; function- (s. of functio ) a performance, execution, equiv. to funct ( us ) (ptp. of fungi ) performed, executed + -ion- -ION ]