unassailable evidence确凿的证据
unassailable argument无懈可击的论点
unassailable to坚不可破
An Unassailable立于
unassailable position不败之地
watertight unassailable invulnerable没有可以被人攻击或挑剔的缝隙
ADJ（形容词） If you describe something or someone as unassailable, you mean that nothing can alter, destroy, or challenge them. 不可改变的; 攻不破的; 不容置疑的
Our seemingly unassailable lead in speciality manufacturing has dwindled.
我们在特殊产品制造上似乎不容置疑的领先优势缩小了。