justify, warrant -- (show to be reasonable or provide adequate ground for; "The emergency does not warrant all of us buying guns"; "The end justifies the means")
justify, vindicate -- (show to be right by providing justification or proof; "vindicate a claim")
apologize, apologise, excuse, justify, rationalize, rationalise -- (defend, explain, clear away, or make excuses for by reasoning; "rationalize the child's seemingly crazy behavior"; "he rationalized his lack of success")
absolve, justify, free -- (let off the hook; "I absolve you from this responsibility")
justify -- (adjust the spaces between words; "justify the margins")