Source : Webster's Revised Unabridged Dictionary (1913)

Discretional \Dis*cre"tion*al\, Discretionary
\Dis*cre"tion*a*ry\, [Cf. F. discr['e]tionnaire.]
   Left to discretion; unrestrained except by discretion or
   judgment; as, an ambassador with discretionary powers.

Source : WordNet®

discretionary
     adj 1: having or using the ability to act or decide according to
            your own discretion or judgment; "The commission has
            discretionary power to award extra funds" [syn: {discretional}]
     2: (especially of funds) not earmarked; available for use as
        needed; "discretionary funds"; "discretionary income"