This is the 7962nd most frequent Portuguese word.
russi
"Russi" is not a standard Portuguese word. It might refer to "Rússia," meaning "Russia" in English. Context is needed for clarification.
In this sentence, 'russos' refers to people from Russia, used as a plural noun.
Os russos gostam de inverno rigoroso.
Russians enjoy harsh winters.
Here, 'russa' describes something related to Russia, used as an adjective.
A música tradicional russa é muito bonita.
Traditional Russian music is very beautiful.
In this context, 'russo' refers to the Russian language, used as a singular noun.