noun (n)

• cautionary advice about something imminent (especially imminent danger or other unpleasantness)(noun.communication)

  Example:
  A letter of admonition about the dangers of immorality.
  

  Synonym:
  monition, warning, word of advice
  

  source: wordnet30
• a firm rebuke(noun.communication)

  Synonym:
  admonishment, monition
  

  source: wordnet30
• Gentle or friendly reproof; counseling against a fault or error; expression of authoritative advice; friendly caution or warning.(noun)

  source: webster1913