Upstart (noun)

1. A person who has recently risen to a higher social or economic status but has not yet gained the respect or recognition of their peers.
2. A person who is newly rich, powerful, or successful, but is considered to be arrogant or presumptuous as a result.

Origin:

Late 16th century (as an adjective in the sense "recently risen in status"): from up + start.

Examples:

1. The wealthy upstart had no idea how to handle his new position of power.
2. He was considered an upstart by his colleagues, having only recently been promoted to a senior position.
3. The upstart company quickly made a name for itself with its innovative products.
4. He was looked down upon by the old guard as an upstart who had not paid his dues.
5. The new leader was seen as an upstart who had risen to the top without any real experience.