eschatologist vs theologian

eschatologist and theologian both are nouns.

Word	Noun	Adjective	Verb	Adverb
eschatologist	Yes	No	No	No
theologian	Yes	No	No	No

As nouns, theologian is a hypernym of eschatologist; that is, theologian is a word with a broader meaning than eschatologist:

eschatologist: a theologian who specializes in eschatology
theologian: someone who is learned in theology or who speculates about theology

Other hypernyms of eschatologist include theologiser, theologist, theologizer.

eschatologist (noun)	theologian (noun)
a theologian who specializes in eschatology	someone who is learned in theology or who speculates about theology