Gerbert vs Sylvester II

Gerbert and Sylvester II both are nouns.

Word	Noun	Adjective	Verb	Adverb
Gerbert	Yes	No	No	No
Sylvester II	Yes	No	No	No

As nouns, Gerbert and Sylvester II are synonyms defined as:

Gerbert and Sylvester II: French pope from 999 to 1003 who was noted for his great learning (945-1003)

Other synonyms of Gerbert include Pope Sylvester II.

Gerbert (noun)	Sylvester II (noun)
French pope from 999 to 1003 who was noted for his great learning (945-1003)	French pope from 999 to 1003 who was noted for his great learning (945-1003)