Source : Webster's Revised Unabridged Dictionary (1913)

Alchemy \Al"che*my\, n. [OF. alkemie, arquemie, F. alchimie, Ar.
   al-k[=i]m[=i]a, fr. late Gr. ?, for ?, a mingling, infusion,
   ? juice, liquid, especially as extracted from plants, fr. ?
   to pour; for chemistry was originally the art of extracting
   the juices from plants for medicinal purposes. Cf. Sp.
   alquimia, It. alchimia. Gr. ? is prob. akin to L. fundere to
   pour, Goth. guitan, AS. ge['o]tan, to pour, and so to E.
   fuse. See {Fuse}, and cf. {Chemistry}.]
   1. An imaginary art which aimed to transmute the baser metals
      into gold, to find the panacea, or universal remedy for
      diseases, etc. It led the way to modern chemistry.

   2. A mixed metal composed mainly of brass, formerly used for
      various utensils; hence, a trumpet. [Obs.]

            Put to their mouths the sounding alchemy. --Milton.

   3. Miraculous power of transmuting something common into
      something precious.

            Kissing with golden face the meadows green, Gilding
            pale streams with heavenly alchemy.   --Shak.

Source : WordNet®

alchemy
     n 1: a pseudoscientific forerunner of chemistry in medieval times
     2: the way two individuals relate to each other; "their
        chemistry was wrong from the beginning -- they hated each
        other"; "a mysterious alchemy brought them together" [syn:
         {chemistry}, {interpersonal chemistry}]