antagonist
//ænˈtæɡ.ə.nɪst//
Noun
antagonistSingular
antagonistsPlural
1
A person who actively opposes or is hostile to someone or something; an adversary.
The hero finally confronted his antagonist in the final chapter.
2
The main character in a story, play, or film who opposes the protagonist or hero.
The antagonist in the movie was a cunning villain who challenged the hero at every turn.
3
A substance that interferes with or inhibits the physiological action of another.
This drug acts as an antagonist to block the receptor.