What does "refractory" mean?

Refractory: Resisting ordinary treatment; difficult of fusion, reduction, or the like; -- said especially of metals and the like, which do not readily yield to heat, or to the hammer; as, a refractory ore.

Additional senses

  1. 2.A refractory person. Bp. Hall.
  2. 3.Refractoriness. [Obs.] Jer. TAylor.
  3. 4.OPottery) A piece of ware covered with a vaporable flux and placed in a kiln, to communicate a glaze to the other articles. Knight.

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