reflexiveness vs coreference

reflexiveness and coreference both are nouns.

Word	Noun	Adjective	Verb	Adverb
reflexiveness	Yes	No	No	No
coreference	Yes	No	No	No

As nouns, coreference is a hypernym of reflexiveness; that is, coreference is a word with a broader meaning than reflexiveness:

reflexiveness: the coreferential relation between a reflexive pronoun and its antecedent
coreference: the grammatical relation between two words that have a common referent

reflexiveness (noun)	coreference (noun)
the coreferential relation between a reflexive pronoun and its antecedent	the grammatical relation between two words that have a common referent
(logic and mathematics) a relation such that it holds between an element and itself