refining industry vs oil industry

refining industry and oil industry both are nouns.

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

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

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

Other synonyms of refining industry include oil business.

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