abstruse

这篇博士论文过于艰深晦涩，甚至连答辩委员会成员也承认很难跟上其中的论证。

The doctoral dissertation was so ___abstruse that even members of the candidate's own committee admitted they struggled to follow the argument.

新实验室设备的技术手册语言过于晦涩，研究团队花了第一周的时间才勉强解读清楚安装说明。

The technical manual for the new laboratory equipment was written in such ___abstruse language that the research team spent the first week just deciphering the setup instructions.

这位哲学家的公开讲座多年来变得越来越玄奥晦涩，反倒疏远了他曾经感染过的那批听众。

The philosopher's public lectures had become increasingly ___abstruse over the years, alienating the very audience he once inspired.