kumis vs koumiss

kumis and koumiss both are nouns.

Word	Noun	Adjective	Verb	Adverb
kumis	Yes	No	No	No
koumiss	Yes	No	No	No

As nouns, kumis and koumiss are synonyms defined as:

kumis and koumiss: an alcoholic beverage made from fermented mare's milk; made originally by nomads of central Asia

kumis (noun)	koumiss (noun)
an alcoholic beverage made from fermented mare's milk; made originally by nomads of central Asia	an alcoholic beverage made from fermented mare's milk; made originally by nomads of central Asia