It will be plain to a Russian (6)
I believe the answer is:
steppe
'it will be plain to a russian' is the definition.
The definition suggests a singular noun which matches the answer.
This is all the clue.
Can you help me to learn more?
(Other definitions for steppe that I've seen before include "Dry grassy plain of central Europe" , "Treeless plain of Russia" , "(Russian) grassy plain" , "Flat area of eastern Europe or Russia" , "Large area of unforested grassland" .)