Refractory

refers to the quality of a material to retain its strength at high temperatures or, more generally, to the tendency to remain unaltered, such as neurons, which are non-responsive to newly incoming stimuli during the refractory period, or primary cells or certain cell lines, which are refractory to transfection or other experimental manipulations

Description
Refractory materials, in the primary sense, are used to make crucibles and linings for furnaces, kilns and incinerators. There is no clearly established boundary between refractory and non-refractory materials, though a practical requirement often cited is the ability of the material to withstand temperatures above 1100 °C without softening.