oil industry vs oil business

oil industry and oil business both are nouns.

Word	Noun	Adjective	Verb	Adverb
oil industry	Yes	No	No	No
oil business	Yes	No	No	No

As nouns, oil industry and oil business are synonyms defined as:

oil industry and oil business: an industry that produces and delivers oil and oil products

Other synonyms of oil industry include refining industry.

oil industry (noun)	oil business (noun)
an industry that produces and delivers oil and oil products	an industry that produces and delivers oil and oil products