steppe vs champaign

steppe and champaign both are nouns.

Word	Noun	Adjective	Verb	Adverb
steppe	Yes	No	No	No
champaign	Yes	No	No	No

As nouns, champaign is a hypernym of steppe; that is, champaign is a word with a broader meaning than steppe:

steppe: extensive plain without trees (associated with eastern Russia and Siberia)
champaign: extensive tract of level open land

Other hypernyms of steppe include field, plain.

steppe (noun)	champaign (noun)
extensive plain without trees (associated with eastern Russia and Siberia)	extensive tract of level open land