Sort of plain (6)
I believe the answer is:
steppe
'sort of plain' is the definition.
(I know that steppe is a type of champaign)
This is the entire clue.
(Other definitions for steppe that I've seen before include "Large area of flat grassland in Europe or Siberia" , "Dry plain of Eurasia" , "Dry grassy plain of central Europe" , "Treeless plain of Russia" , "Dry area of grassland in southeast Europe and Siberia" .)