sweetie vs sugar daddy

sweetie and sugar daddy both are nouns.

Word	Noun	Adjective	Verb	Adverb
sweetie	Yes	No	No	No
sugar daddy	Yes	No	No	No

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

sweetie: a person loved by another person
sugar daddy: a wealthy older man who gives a young person expensive gifts in return for friendship or intimacy

Other hyponyms of sweetie include dulcinea, ladylove, valentine.

sweetie (noun)	sugar daddy (noun)
a person loved by another person	a wealthy older man who gives a young person expensive gifts in return for friendship or intimacy
a beloved person; used as terms of endearment