noun (n)

• insistent solicitation and entreaty(noun.communication)

  Example:
  His importunity left me no alternative but to agree.
  

  Synonym:
  urgency, urging
  

  source: wordnet30
• The quality of being importunate; pressing or pertinacious solicitation; urgent request; incessant or frequent application; troublesome pertinacity.(noun)

  source: webster1913