sweetener vs aspartame

sweetener and aspartame both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweetener	Yes	No	No	No
aspartame	Yes	No	No	No

As nouns, aspartame is a hyponym of sweetener; that is, aspartame is a word with a more specific, narrower meaning than sweetener:

sweetener: something added to foods to make them taste sweeter
aspartame: an artificial sweetener made from aspartic acid; used as a calorie-free sweetener

Other hyponyms of sweetener include honey, saccharin, refined sugar, sugar, sirup, syrup, cyclamate.

sweetener (noun)	aspartame (noun)
anything that serves as an enticement	an artificial sweetener made from aspartic acid; used as a calorie-free sweetener
something added to foods to make them taste sweeter