deadlyadjective
enemy
The pine marten hunts in trees and is the deadly enemy of squirrels and birds.
The two boys were deadly enemies at school, but now they seem to get on much better.
The local people believed that their gods protected them from their deadly enemies.
SMART Vocabulary: related words and phrases
Enemies & rivals
adversary
antagonist
arch-enemy
enemy
foe
frenemy
nemesis
opponent
rival
scalp
sworn enemy
them
them and usidiom