in-,进入，使，-sid,坐，词源同sit,sedentary.即坐在里边的，引申词义潜伏的。

1. They focus on overt discrimination rather than insidious aspects of racism.

他们关注的是公开的歧视，而不是种族主义的一些潜在问题。

2. the insidious effects of polluted water supplies

供水系统污染的潜在恶果

3. The changes are insidious, and will not produce a noticeable effect for 15 to 20 years.

变化是悄然发生的,15到20年间不会产生明显影响。

4. Organized crime has an insidious influence on all who come into contact with it.

所有和集团犯罪有关的人都会不知不觉地受坏影响.

5. That insidious man bad mouthed me to almost everyone else.

那个阴险的家伙几乎见人便说我的坏话。