Prince Nikolai Sergeyevich Trubetzkoy (Russian: ??????´? ?????´???? ????????´?, IPA: [tr?b??ts'koj]; Moscow, April 16, 1890 – Vienna, June 25, 1938) was a Russian linguist and historian whose teachings formed a nucleus of the Prague School of structural linguistics.
He is widely considered to be the founder of morphophonology.
He was also associated with the Russian Eurasianists.