All 4 Uses

function
in
East of Eden
(Edited)

In feudal times an ineptness with sword and spear headed a young man for the church: in the Hamilton family Joe's inability properly to function at farm and forge headed him for a higher education.
Chpt 5

function = work
In their millions the frog songs seemed to have a beat and a cadence, and perhaps it is the ears' function to do this just as it is the eyes' business to make stars twinkle.
Chpt 36

function = job
That is only natural, just as it is natural for a man whose life function is the making of money to make money out of a war.
Chpt 46 *

function = purpose
Her mind functioned like a wooden mind, her body moved crookedly like a badly operated marionette, but she went steadily about her business.
Chpt 50 *

functioned = worked or operated

Definitions:

(1) (function as in: Its main function is to...)
purpose, job, or natural activity
(2) (function as in: can't function well without sleep)
work or operate -- sometimes to work or operate normally or in a particular way
(3) (function as in: I'm attending a function tonight)
a social event or ceremony -- especially one attended for work or out of a sense of duty
(4) (function as in: oxygen is a function of altitude)
saying one results from another; or saying that the amount of one thing is dependent upon the value of another.

If x is a function of y, then x results from y; or the amount of x can be calculated based on the amount of y.
(5) (function as in: Amazon's new search function)
computer code that performs a specific task
(6) (function as in: a mathematical function)
a formula or mathematical expression that describes a relationship between variables
(7) (meaning too rare to warrant focus)
For more specialized meanings in math and chemistry, see a comprehensive dictionary.