authority figure; person of authority
Refers to a person who holds recognized expertise, power, or influence in a particular field or context.
He is known as an authority in this field.
The decision was made by an authority figure.
専門家 emphasizes specialized knowledge or expertise, whereas 権威者 carries a stronger connotation of recognized power or influence in addition to expertise.
Compound of 権威 (authority, prestige) and 者 (person). The exact historical derivation is uncertain, but the word follows a common Sino-Japanese pattern for forming agent nouns.