Not obligate; optional, discretionary or elective.
That grants permission or power to do something.
Able to perform a particular life function, or to live generally, in more than one way.
Of or relating to faculty, especially to mental faculty.
At which a given function is positive.
Not elaborated upon, or not accompanied by restrictions or qualification; undescribed.
Outright; thorough; utter.
Not qualified, ineligible, unfit for a position or task.