The monomaniac is unbalanced in just one area on everything else except his own pet and particular delusion he may be completely normal.

偏执狂患者，指一个人在某一方面不正常；除了他自己的特别的幻觉以外，他在其它各个方面都完全正常。

youdao

A few more meetings completely removed from Narendra's mind the last traces of the notion that Sri Ramakrishna might be a monomaniac or wily hypnotist.

几次见面之后，纳兰德心中完全消除了有关室利罗摩·克里希纳是偏执狂和老谋深算的催眠士的疑惑。

youdao

An admitted monomaniac on the subject of parking tickets, he races through calculations.

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