ingenue (n.) Look up ingenue at Dictionary.com
"young woman who displays innocent candor or simplicity," 1848, from French ingénue "artless girl," especially as a character on the stage, noun use of fem. of ingénu "ingenuous, artless, simple" (13c.), from Latin ingenuus "frank, upright, candid," originally "free-born" (see ingenuous). Italicized in English into 20c.