Ingrian vs Ingerman

Ingrian and Ingerman both are nouns.

Word	Noun	Adjective	Verb	Adverb
Ingrian	Yes	No	No	No
Ingerman	Yes	No	No	No

As nouns, Ingrian and Ingerman are synonyms defined as:

Ingrian and Ingerman: a member of western Finnish people formerly living in the Baltic province where Saint Petersburg was built

Other synonyms of Ingrian include Inger.

Ingrian (noun)	Ingerman (noun)
a Finnic language spoken by the Ingrian	a member of western Finnish people formerly living in the Baltic province where Saint Petersburg was built
a member of western Finnish people formerly living in the Baltic province where Saint Petersburg was built