[na.ive] adj na.iv.er ; -est [F naive, fem. of naif, fr. OF, inborn, natural, fr. L nativus native] (1654) 1: marked by unaffected simplicity: artless, ingenuous
2. a: deficient in worldly wisdom or informed judgment; esp: credulous b: not previously subjected to experimentation or a particular experimental situation "made the test with ~ rats"; also: not having previously used a particular drug (as marijuana)
3: self-taught, primitive syn see natural -- na.ive.ly adv -- na.ive.ness n