antagonist
UK: ænˈtæɡənɪst | US: ænˈtæɡənɪst
n. a person who actively opposes or is hostile to someone or something; an adversary.
n. (Biochemistry) a substance that interferes with or inhibits the physiological action of another.
n. (Anatomy) a muscle whose action counteracts that of another muscle.
The word "antagonist" originates from Greek antagōnistēs, combining anti- (against) + agōn (contest, struggle). The root agōn reflects ancient Greek competitive events, evolving metaphorically to denote opposition. The suffix -ist denotes an agent, forming "one who opposes." Over time, the term expanded from literal competitors (e.g., in drama or sports) to broader contexts of conflict in biology, chemistry, and social dynamics.
The protagonist faced his antagonist in the final battle.
In the play, Iago serves as the cunning antagonist to Othello.
This drug acts as an antagonist to block the receptor’s activity.
The triceps muscle is the antagonist to the biceps during flexion.
She viewed the new policy as an antagonist to her personal freedoms.