theologian vs theologiser

theologian and theologiser both are nouns.

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

As nouns, theologian and theologiser are synonyms defined as:

theologian and theologiser: someone who is learned in theology or who speculates about theology

Other synonyms of theologian include theologist, theologizer.

theologian (noun)	theologiser (noun)
someone who is learned in theology or who speculates about theology	someone who is learned in theology or who speculates about theology