noun
cynic
SIN-ik/ˈsɪnɪk/
A person who expects others to act from selfish or dishonest motives.
A cynic assumes the generous donation is just a publicity stunt.

Etymology
The 'dog-like' label first named Antisthenes' followers, more likely after his teaching place, 'The Gray Dog,' than their reputed surliness. It later meant a sneering person, leading to today's distrustful sense.
In context
paranoid, transactional cynic who measures love in obedience.
More examples
- Even a cynic can recognize a genuinely kind gesture.
- The office cynics suspect the boss's praise is a way to avoid raises.
- Call me a cynic, but I think he wants something in return.
Forms
cynic · cynics
cynical adjective — Distrustful of other people's motives.
cynicism noun — The belief that people act selfishly.