refractory
/rɪˈfræktərɪ; rɪ`fræktərɪ/ adj
1 (fml 文) difficult to control or discipline; wilful or unmanageable 难控制的; 不听管教的; 任性的; 难管理的
a very refractory child 很不听话的孩子.
2 (of a disease, etc) not yielding to treatment （指疾病等）难治的.
3 (of substances, metals, etc) difficult to fuse or work; resistant to heat （指物质、 金属等）难熔的; 难处理的; 耐热的
refractory brick, eg in furnace linings 耐火砖.