Get the FREE one-click dictionary software for Windows
or the iPhone/iPad and Android apps
Adjective: importunate  im'por-tyû-nut or im'por-chu-nut
  1. Persistent to the point of annoying
    "The importunate salesman refused to take no for an answer"
     
  2. Persistent or demanding, esp. annoyingly so
    "an importunate job applicant"

See also: beseeching, imploring, pleading