Adjective naive has 3 senses
  1. naive, naif - marked by or showing unaffected simplicity and lack of guile or worldly experience; "a teenager's naive ignorance of life"; "the naive assumption that things can only get better"; "this naive simple creature with wide friendly eyes so eager to believe appearances"
    Antonyms: sophisticated, blase, worldly, intelligent, well-informed, polished, refined, svelte, urbane, worldly-wise
  2. callow, inexperienced, naive, unsophisticated - lacking experience of life; "a callow youth of seventeen"
    Antonym: mature (indirect, via immature)
  3. naive, unsophisticated - lacking sophistication
    Antonym: artful (indirect, via artless)