industry expert
Refers to a person with deep knowledge of a particular industry, often used in business or computing contexts.
He is known as an industry expert in the IT field.
The opinion of an industry expert is essential for developing new products.
専門家 is a general term for a specialist or expert in any field, while 業界精通者 specifically emphasizes deep knowledge of a particular industry.
Compound of 業界 (industry) + 精通 (expert knowledge) + 者 (person). The exact historical derivation is uncertain, but the word follows a common pattern for forming agent nouns.