Source : Webster's Revised Unabridged Dictionary (1913)

Excusable \Ex*cus"a*ble\a. [L. excusabilis: cf. F. excusable.
   See {Excuse}.]
   That may be excused, forgiven, justified, or acquitted of
   blame; pardonable; as, the man is excusable; an excusable
   action. -- {Ex*cus"a*ble*ness}, n. -- {Ex*cus"a*bly}, adv.

         The excusableness of my dissatisfaction. --Boyle.

Source : WordNet®

excusable
     adj 1: capable of being overlooked [ant: {inexcusable}]
     2: easily excused or forgiven; "a venial error" [syn: {forgivable},
         {venial}]