pickle \pic"kle\, n. cf. d. pekel. probably a dim. fr. pick,
   v. t., alluding to the cleaning of the fish.
   1.
      a a solution of salt and water, in which fish, meat,
          etc., may be preserved or corned; brine.
      b vinegar, plain or spiced, used for preserving
          vegetables, fish, eggs, oysters, etc.
          1913 webster

   2. any article of food which has been preserved in brine or
      in vinegar.
      1913 webster

   3. founding a bath of dilute sulphuric or nitric acid,
      etc., to remove burnt sand, scale rust, etc., from the
      surface of castings, or other articles of metal, or to
      brighten them or improve their color.
      1913 webster

   4. a troublesome child; as, a little pickle. colloq.
      1913 webster

   to be in a pickle, to be in disagreeable position; to be in
      a condition of embarrassment, difficulty, or disorder.
      "how cam'st thou in this pickle?" --shak.

   to put a rod in pickle, to prepare a particular reproof,
      punishment, or penalty for future application.
      1913 webster
see also:
pick to be in a pickle to put a rod in pickle