Mstislav Look up Mstislav at Dictionary.com
Slavic masc. proper name, literally "vengeful fame," from Russian mstit' "to take revenge," from Proto-Slavic *misti "revenge," *mistiti "to take revenge," from PIE *mit-ti-, extended form of root *mei- (1) "to change, go, move" (see mutable); for second element, see Slav.