verb (v)

• deliver by singing(verb.creation)

  Example:
  Sing Christmas carols.
  

  source: wordnet30
• produce tones with the voice(verb.creation)

  Example:
  She was singing while she was cooking.
  My brother sings very well.
  

  source: wordnet30
• to make melodious sounds(verb.communication)

  Example:
  The nightingale was singing.
  

  source: wordnet30
• make a whining, ringing, or whistling sound(verb.communication)

  Example:
  The kettle was singing.
  

  Synonym:
  whistle
  

  source: wordnet30
• divulge confidential information or secrets(verb.communication)

  Synonym:
  babble, babble out, blab, blab out, let the cat out of the bag, peach, spill the beans, talk, tattle
  Antonym:
  keep one's mouth shut, keep quiet, shut one's mouth
  

  source: wordnet30
• To utter sounds with musical inflections or melodious modulations of voice, as fancy may dictate, or according to the notes of a song or tune, or of a given part (as alto, tenor, etc.) in a chorus or concerted piece.(verb)

  source: webster1913
• To utter with musical inflections or modulations of voice.(verb)

  source: webster1913