lover vs groupie

lover and groupie both are nouns.

Word	Noun	Adjective	Verb	Adverb
lover	Yes	No	No	No
groupie	Yes	No	No	No

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

lover: an ardent follower and admirer
groupie: an enthusiastic young fan (especially a young woman who follows rock groups around)

lover (noun)	groupie (noun)
a person who loves someone or is loved by someone	an enthusiastic young fan (especially a young woman who follows rock groups around)
an ardent follower and admirer
a significant other to whom you are not related by marriage