What Does It Mean?

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From our dictionary:

adj., n., pl. -ries.


1. hard or impossible to manage; stubbornly disobedient: a refractory child.
2. resisting ordinary methods of treatment.
3. Obs.difficult to fuse, reduce, or work, as an ore or metal.

1. a material having the ability to retain its physical shape and chemical identity when subjected to high temperatures.
2. refractories, bricks of various shapes used in lining furnaces.