- hard to manage; stubborn; obstinate: said of a person or animal
- resistant to heat; hard to melt or work: said of ores or metals
- not yielding to treatment, as a disease
- able to resist disease
altered < obs. refractary < L refractarius < refractus: see refract
noun pl. refractories
something refractory; specif., a heat-resistant material used in lining furnaces, etc.