adjective / noun
phony
FOH-nee/ˈfəʊni/
Not genuine or sincere.
The ring's phony gold surface flakes away to reveal gray metal.

Etymology
Phony may be an alteration of fawney, a gilt brass ring used by swindlers. If that connection is correct, a deceptive object supplied the broader idea of something fake or insincere.
In context
they feel inadequate they feel phony the Imposter syndrome they feel fake inferior and deserving of punishment
More examples
- The email directs me to a phony banking website.
- He calls himself an expert, but he's a phony.
- His excuse sounds even phonier the second time.
Forms
phony · phonies · phonier · phoniest
phoniness noun — The quality of being fake or insincere.
Similar words
- fake
- Broadly describes something made to appear real when it is not.
- fraudulent
- Specifically involves deliberate deception, often for money or other gain.
- insincere
- Describes feelings or statements that are not honestly meant.