A person who has risen, climbed up, or has been promoted to a higher social class, especially through acquisition of wealth, rights, or political authority but has not gained social acceptance by those within that new class.
User Defined Definitions
"a person who has suddenly risen to a higher economic status but has not gained social acceptance of others in that class"
"characteristic of someone who has risen economically or socially but lacks the social skills appropriate for this new position"