What is the meaning of justify?

verb

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