Byelorussia vs Belorussia

Byelorussia and Belorussia both are nouns.

Word	Noun	Adjective	Verb	Adverb
Byelorussia	Yes	No	No	No
Belorussia	Yes	No	No	No

As nouns, Byelorussia and Belorussia are synonyms defined as:

Byelorussia and Belorussia: a landlocked republic in eastern Europe; formerly a European soviet

Other synonyms of Byelorussia include Belarus, Byelarus, Republic of Belarus, White Russia.

Byelorussia (noun)	Belorussia (noun)
a landlocked republic in eastern Europe; formerly a European soviet	a landlocked republic in eastern Europe; formerly a European soviet