oil cartel vs corporate trust

oil cartel and corporate trust both are nouns.

Word	Noun	Adjective	Verb	Adverb
oil cartel	Yes	No	No	No
corporate trust	Yes	No	No	No

As nouns, corporate trust is a hypernym of oil cartel; that is, corporate trust is a word with a broader meaning than oil cartel:

oil cartel: a cartel of companies or nations formed to control the production and distribution of oil
corporate trust: a consortium of independent organizations formed to limit competition by controlling the production and distribution of a product or service

Other hypernyms of oil cartel include cartel, combine, trust.

oil cartel (noun)	corporate trust (noun)
a cartel of companies or nations formed to control the production and distribution of oil	a consortium of independent organizations formed to limit competition by controlling the production and distribution of a product or service