A person who pretends to be of a higher social class than they really are.
This word can make people think of pretending, social class, and maybe a little bit of silliness.
Examples:
The slummer wore fancy clothes to the party.
She's a slummer, but she's really just a regular person.
The slummer acted like she was a queen.
The slummer tried to speak with a fancy accent, but it didn't work.
He's such a slummer, he even pretends to have a butler!
The slummer went to the party and tried to act like a king.