D defs.my
Entry 1 sense Webster, 1913

Water sapphire

/wôt'-ẽr săf'-ī-ẽr/ · Wa·ter sap·phire · IPA
01 A deep blue variety of iolite, sometimes used as a gem; -- called also saphir d'eau.
  1. 1.
    A deep blue variety of iolite, sometimes used as a gem; -- called also saphir d'eau.(Min.) Also: saphir d'eau