noun (n)

• extreme dullness; lacking spirit or interest(noun.attribute)

  Synonym:
  boringness, dreariness, insipidness
  

  source: wordnet30
• lacking any distinctive or interesting taste property(noun.attribute)

  Synonym:
  blandness, insipidness
  

  source: wordnet30
• The quality or state of being insipid; vapidity.(noun)

  source: webster1913