mortal enemy
Noun
Meaning
an enemy who wants to kill you
Source: WordNetSynonyms
Antonyms
Hypernyms
Examples
A pitcher has to look at the hitter as his mortal enemy.
One grasps incomparably more things in boredom than by labor, effort being the mortal enemy of meditation.
I guess intractable right-wing ideologues are my mortal enemy.
I see corruption as a mortal enemy for young democracies.
You have lent and not recovered; and if recovered, not so much; and if so much, not such; and if such, a mortal enemy.
Luck is the friend of jackasses and the crazy; it's a mortal enemy of the virtuous.