Ingenue

in·gé·nue

         

    /ˈænʒəˌnu, -ˌnyu; Fr. ɛ̃ʒeɪˈnü/ Show Spelled /-ˌnuz, -ˌnyuz; Fr. -ˈnü

1.   the part of an artless, innocent, unworldly girl or young woman, esp. as represented on the stage.

2.  an actress who plays such a part or specializes in playing such parts.

Also, in·ge·nue.