noun

1. an early form of chemistry, with philosophic and magical associations, studied in the Middle Ages: its chief aims were to change base metals into gold and to discover the elixir of perpetual youth
2. a power or process of changing one thing into another; esp., a seemingly miraculous power or process of changing a thing into something better

Etymology: ME alchymie < OFr alchimie < ML alchemia < Ar al-kīmiyāʾ < Gr chēmeia < ? Chēmia, old name for Egypt < Egyptian kmt, lit., black (land); infl. by folk-etym. assoc. with Gr cheein, to pour: see found