Maghreb vs Greater Maghreb

Maghreb and Greater Maghreb both are nouns.

Word	Noun	Adjective	Verb	Adverb
Maghreb	Yes	No	No	No
Greater Maghreb	Yes	No	No	No

As nouns, Maghreb and Greater Maghreb are synonyms defined as:

Maghreb and Greater Maghreb: the region of northwest Africa comprising the Atlas Mountains and the coastlands of Morocco and Algeria and Tunisia

Other synonyms of Maghreb include Mahgrib.

Maghreb (noun)	Greater Maghreb (noun)
the region of northwest Africa comprising the Atlas Mountains and the coastlands of Morocco and Algeria and Tunisia	the region of northwest Africa comprising the Atlas Mountains and the coastlands of Morocco and Algeria and Tunisia