Bigwig (noun)

1. An important or powerful person.
2. A person of high rank or standing in an organization or profession.

Origin:

18th century: from big "important" + wig, as worn by men of importance in the 17th and 18th centuries.

Examples:

1. He's a bigwig in the finance industry.
2. The meeting was attended by several bigwigs from the company.
3. The politician is a bigwig in his party.
4. The lawyer is a bigwig in the legal profession.
5. The scientist is a bigwig in his field.