 
 
fixed point (mathematics)    The fixed point of a function, f is any value, x for which f x = x.  A function may have any number of fixed points from none (e.g. f x = x+1) to infinitely many (e.g. f x = x).  The fixed point combinator, written as either "fix" or "Y" will return the fixed point of a function. 
See also least fixed point. Last updated: 1995-04-13