Belarus vs Republic of Belarus

Belarus and Republic of Belarus both are nouns.

Word	Noun	Adjective	Verb	Adverb
Belarus	Yes	No	No	No
Republic of Belarus	Yes	No	No	No

As nouns, Belarus and Republic of Belarus are synonyms defined as:

Belarus and Republic of Belarus: a landlocked republic in eastern Europe; formerly a European soviet

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

Belarus (noun)	Republic of Belarus (noun)
a landlocked republic in eastern Europe; formerly a European soviet	a landlocked republic in eastern Europe; formerly a European soviet