unjustifiable

adjective

1. capable of being justified; that can be shown to be or can be defended as being just, right, or warranted; defensible: justifiable homicide.

adjective

1. not capable of being justified

adjective

1. capable of being justified; understandable

adj.1640s, from un- (1) “not” + justifiable. Related: Unjustifiably. adj.1520s, from Old French justifiable, from justifiier (see justify). Earlier in same sense was justificable (mid-15c.). Related: Justifiably (mid-15c.).