危害物;大敌
something that harms something else
Familiarity is the enemy of desire. 习以为常，则无所欲求。
You shouldn't allow perfection to be the enemy of the good.
Delay is the enemy of reform.
It is a gift to be intelligent, dear girl, but to many suitors, wit is the enemy of charm.
A prominent cultural critic, he once proclaimed that rationality was the enemy of true art.
See also: enemy