n. the act of defending or explaining or making excuses for by reasoning; "the justification of barbarous means by holy ends"- H.J.Muller

n. something (such as a fact or circumstance) that shows an action to be reasonable or necessary; "he considered misrule a justification for revolution"

n. a statement in explanation of some action or belief

n. [the act of giving reasons for a particular act or behavior]

n. the alignment of text evenly between left and right margins