D defs.my
Entry 2 senses Webster, 1913

Zircon

/zẽrk'-ən/ · Zir·con · IPA /ˈzɜː(ɹ)kən/
01 n. A mineral consisting predominantly of zirconium silicate (Zr2SiO4) occurring in tetragonal crystals, usually of a brown or gray color. It c…
  1. 1.
    A mineral consisting predominantly of zirconium silicate (Zr2SiO4) occurring in tetragonal crystals, usually of a brown or gray color. It consists of silica and zirconia. A red variety, used as a gem, is called hyacinth. Colorless, pale-yellow or smoky-brown varieties from Ceylon are called jargon.(Min.)
  2. 2.
    an imitation gemstone made of cubic zirconia.
Phrases & compounds
Zircon syenite — a coarse-grained syenite containing zircon crystals and often also elaeolite. It is largely developed in Southern Norway.