verb (v)

• acknowledge faults or shortcomings or failing(verb.communication)

  Example:
  I apologized for being late.
  He apologized for the many typoes.
  

  Synonym:
  apologise
  

  source: wordnet30
• defend, explain, clear away, or make excuses for by reasoning(verb.communication)

  Synonym:
  apologise, excuse, justify, rationalise, rationalize
  

  source: wordnet30
• To make an apology or defense.(verb)

  source: webster1913
• To defend.(verb)

  source: webster1913