The Collaborative International Dictionary of English v.0.48:

Ing'enue \In`g['e]`nue"\ ([a^]N`zh[asl]`n[.u]"), n.; pl.
   -nues. [F., fem. of ing['e]nu ingenious.]
   An ingenuous or na["i]ve girl or young woman, or an actress
   representing such a person.
   [Webster 1913 Suppl.]