lover vs baby

lover and baby both are nouns.

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

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

lover (noun)	baby (noun)
a person who loves someone or is loved by someone	a project of personal concern to someone
an ardent follower and admirer	a very young mammal
a significant other to whom you are not related by marriage	a very young child (birth to 1 year) who has not yet begun to walk or talk
	the youngest member of a group (not necessarily young)
	an immature childish person
	an unborn child; a human fetus
	a beloved person; used as terms of endearment

lover (verb)	baby (verb)
	treat with excessive indulgence