The Collaborative International Dictionary of English v.0.48:

Gentle \Gen"tle\, a. [Compar. Gentler; superl. Gentlest.]
   [OE. gentil, F. gentil noble, pretty, graceful, fr. L.
   gentilis of the same clan or race, fr. gens, gentis, tribe,
   clan, race, orig. that which belongs together by birth, fr.
   the root of genere, gignere, to beget; hence gentle,
   properly, of birth or family, that is, of good or noble
   birth. See Gender, and cf. Genteel, Gentil, Gentile,
   Gentoo, Jaunty.]
   1. Well-born; of a good family or respectable birth, though
      not noble.
      [1913 Webster]

            British society is divided into nobility, gentry,
            and yeomanry, and families are either noble, gentle,
            or simple.                            --Johnson's
                                                  Cyc.
      [1913 Webster]

            The studies wherein our noble and gentle youth ought
            to bestow their time.                 --Milton.
      [1913 Webster]

   2. Quiet and refined in manners; not rough, harsh, or stern;
      mild; meek; bland; amiable; tender; as, a gentle nature,
      temper, or disposition; a gentle manner; a gentle address;
      a gentle voice.
      [1913 Webster]

   3. A compellative of respect, consideration, or conciliation;
      as, gentle reader. "Gentle sirs." "Gentle Jew." "Gentle
      servant." --Shak.
      [1913 Webster]

   4. Not wild, turbulent, or refractory; quiet and docile;
      tame; peaceable; as, a gentle horse.
      [1913 Webster]

   5. Soft; not violent or rough; not strong, loud, or
      disturbing; easy; soothing; pacific; as, a gentle touch; a
      gentle gallop . "Gentle music." --Sir J. Davies.
      [1913 Webster]

            O sleep! it is a gentle thing.        --Coleridge.
      [1913 Webster]

   The gentle craft, the art or trade of shoemaking.

   Syn: Mild; meek; placid; dovelike; quiet; peaceful; pacific;
        bland; soft; tame; tractable; docile.

   Usage: Gentle, Tame, Mild, Meek. Gentle describes the
          natural disposition; tame, that which is subdued by
          training; mild implies a temper which is, by nature,
          not easily provoked; meek, a spirit which has been
          schooled to mildness by discipline or suffering. The
          lamb is gentle; the domestic fowl is tame; John, the
          Apostle, was mild; Moses was meek.
          [1913 Webster]