Great Mother vs Magna Mater

Great Mother and Magna Mater both are nouns.

Word	Noun	Adjective	Verb	Adverb
Great Mother	Yes	No	No	No
Magna Mater	Yes	No	No	No

As nouns, Great Mother and Magna Mater are synonyms defined as:

Great Mother and Magna Mater: great nature goddess of ancient Phrygia in Asia Minor; counterpart of Greek Rhea and Roman Ops

Other synonyms of Great Mother include Cybele, Dindymene, Mater Turrita.

Great Mother (noun)	Magna Mater (noun)
great nature goddess of ancient Phrygia in Asia Minor; counterpart of Greek Rhea and Roman Ops	great nature goddess of ancient Phrygia in Asia Minor; counterpart of Greek Rhea and Roman Ops