Phony means fake. A phony thing is not real, or it’s a bad imitation of something original. A phony person does not present himself or herself honestly. You can use "phony" as an adjective or as a noun.
That guy is so phony. (adjective)
He’s a big phony. (noun)
Tanya doesn’t really love her husband. Their marriage is phony.
Richard didn’t really make over a million dollars last year. His claims of success were phony.
Melissa created a phony degree for herself in order to convince others that she graduated from college.
People who are materialistic and superficial are phony.
The offer that we received in the mail promised us big profits on an investment. The offer turned out to be phony.
It was a phony offer.
A person who makes phony promises is a liar.
A person who sells phony merchandise is a swindler and a cheat.
A person who makes phony money is called a counterfeiter.
If you share personal information on a phony website, you might have your identity stolen.
He made a bunch of phony promises to people in order to get elected.