Antagonist
The character or force that opposes the protagonist and creates conflict.
An antagonist blocks the protagonist’s goals, and may be a person, a group, society, nature, or an inner flaw. Writers use the antagonist to generate tension and to test the protagonist’s values. A compelling antagonist gives the central conflict weight and stakes.
Example
The true antagonist is less a single villain than the controlling “rest cure” and her husband’s well-meaning dismissal, forces that confine the narrator.
The Yellow Wallpaper · Charlotte Perkins Gilman