inexpugnable
[,inik'spʌɡnəbl]
adj. 攻不破的；难推翻的；不可战胜的；稳定不变的
同义词
参考例子
1.Therefore the mind which is free from passions is a citadel, for man has nothing more secure to which he can fly for, refuge and for the future be inexpugnable.
所以，那摆脱了激情的心灵就是一座堡垒，因为人再没有什么比这更安全的。
英文解释
adj.
1.incapable of being overcome, challenged or refuted
网络释义
inexpugnable
不能攻占的; 攻不破; 攻不破的; 不坳摇的;
inexpugnable irrefutable
不能驳倒的;