The most common and most likely answer to this crossword clue is the 7 letter word COSSACK
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Buddy explains!
The straight part
We know that "Russian" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case russian = cossack.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does COSSACK mean?
COSSACK noun- A member or descendant of an originally (semi-)nomadic population of Eastern Europe and the adjacent parts of Asia, formed in part of runaways from the neighbouring countries, that eventually settled in parts of the Polish-Lithuanian Commonwealth and the Russian tsarist Empire (where they constituted a legendary military caste), particularly in areas now comprising southern Russia and Ukraine.
- A member of a military unit (typically cavalry, originally recruited exclusively from the above)
- A Ukrainian.