[1] : The Collaborative International Dictionary of English v.0.48

foil \foil\, n. oe. foil leaf, of. foil, fuil, fueil, foille,
   fueille, f. feuille, fr. l. folium, pl. folia; akin to gr. ?,
   and perh. to e. blade. cf. foliage, folio.
   1. a leaf or very thin sheet of metal; as, brass foil; tin
      foil; gold foil.
      1913 webster

   2. jewelry a thin leaf of sheet copper silvered and
      burnished, and afterwards coated with transparent colors
      mixed with isinglass; -- employed by jewelers to give
      color or brilliancy to pastes and inferior stones. --ure.
      1913 webster

   3. anything that serves by contrast of color or quality to
      adorn or set off another thing to advantage.
      1913 webster

            as she a black silk cap on him began
            to set, for foil of his milk-white to serve. --sir
                                                  p. sidney.
      1913 webster

            hector has a foil to set him off.     --broome.
      1913 webster

   4. a thin coat of tin, with quicksilver, laid on the back of
      a looking-glass, to cause reflection.
      1913 webster

   5. arch. the space between the cusps in gothic
      architecture; a rounded or leaflike ornament, in windows,
      niches, etc. a group of foils is called trefoil,
      quatrefoil, quinquefoil, etc., according to the number of
      arcs of which it is composed.
      1913 webster

   foil stone, an imitation of a jewel or precious stone.
      1913 webster
see also:
foliage folio foil stone 

Foil >> F Words
Foil, definition of term: Foil
foil_pag1.html

Blarney Stone >> B Words
Blarney Stone, definition of term: Blarney Stone
blarney+stone_pag1.html

Aluminum Foil >> A Words
Aluminum Foil, definition of term: Aluminum Foil
aluminum+foil_pag1.html

Big Stone Gap >> B Words
Big Stone Gap, definition of term: Big Stone Gap
big+stone+gap_pag1.html