From Old East Slavic вꙑ- (vy-), from Proto-Slavic *vy- (“out”), from Proto-Indo-European *úd, or Proto-Indo-European *(H)ud (Derksen), or *ūd- : *ūt- (Černyx). In Slavic, the final consonant was dropped.
вы́- • (vý-) (this prefix almost invariably bears the stress in perfective verbs, but not in imperfective verbs)
- (used with verbs) out, out from (describing an action of moving outside from inside)
- (used with verbs) completion or fulfillment
- Vasmer, Max (1964–1973), “вы-”, in Этимологический словарь русского языка [Etymological Dictionary of the Russian Language] (in Russian), translated from German and supplemented by Oleg Trubachyov, Moscow: Progress
- Chernykh, Pavel (1999), “вы-”, in Историко-этимологический словарь русского языка [Historical-Etymological Dictionary of the Russian Language] (in Russian), volume 2, 3rd reprint edition, Moscow: Russian Language, page 173