sweetener vs sugar

sweetener and sugar both are nouns.

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

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

sweetener: something added to foods to make them taste sweeter
sugar: a white crystalline carbohydrate used as a sweetener and preservative

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

sweetener (noun)	sugar (noun)
anything that serves as an enticement	a white crystalline carbohydrate used as a sweetener and preservative
something added to foods to make them taste sweeter	informal terms for money
	an essential structural component of living cells and source of energy for animals; includes simple sugars with small molecules as well as macromolecular substances; are classified according to the number of monosaccharide groups they contain

sweetener (verb)	sugar (verb)
	sweeten with sugar