having two parts that do not match exactly, either when one half is not like an image of the other half in a mirror, or when one part cannot take the place of another if it is turned 90° or 180°

He has a non-symmetrical face with one ear higher than the other.

Although the pattern on the carpet appears symmetrical, if you look carefully you can see that it's actually non-symmetrical. 虽然地毯上的图案看起来是对称的，但如果仔细观察，就会发现它实际上是不对称的。

involving actions or parts that are not similar or balanced

The principle of non-symmetrical disarmament has been proposed, where the country with the most weapons cuts the most.

The non-symmetrical distribution means that the results must be treated with caution. 非均衡分布意味着必须谨慎对待结果。