sesame oil vs vegetable oil

sesame oil and vegetable oil both are nouns.

Word	Noun	Adjective	Verb	Adverb
sesame oil	Yes	No	No	No
vegetable oil	Yes	No	No	No

As nouns, vegetable oil is a hypernym of sesame oil; that is, vegetable oil is a word with a broader meaning than sesame oil:

sesame oil: oil obtained from sesame seeds
vegetable oil: any of a group of liquid edible fats that are obtained from plants

Other hypernyms of sesame oil include oil.

sesame oil (noun)	vegetable oil (noun)
oil obtained from sesame seeds	any of a group of liquid edible fats that are obtained from plants