doll vs rag doll

doll and rag doll both are nouns.

Word	Noun	Adjective	Verb	Adverb
doll	Yes	No	No	No
rag doll	Yes	No	No	No

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

Other hyponyms of doll include golliwog, golliwogg, kachina, paper doll, puppet, sawdust doll, toy soldier.

doll (noun)	rag doll (noun)
a small replica of a person; used as a toy	a cloth doll that is stuffed and (usually) painted
informal terms for a (young) woman