Parvenu (noun)

A person who has recently risen to a higher social or economic status but has not yet fully assimilated the manners or customs of that status.

Origin:

From the french word "parvenu" meaning "one who has recently achieved wealth or power".

Examples:

1. He was considered a parvenu by the members of the old money society.
2. She was a parvenu, her family had recently come into money.
3. The parvenu's lack of social graces was obvious at the fancy party.
4. He was a self-made man and a parvenu in the world of high society.
5. The nouveau riche parvenu was trying to buy his way into the elite social circle.