From Longman Dictionary of Contemporary Englishsuzeraintysu‧ze‧rainty /ˈsuːzəreɪnti $ -rənti, -reɪnti/ noun [uncountable] formal PGthe right of a country or leader to rule over another country
Examples from the Corpus
suzerainty• To the east lay border regions - Berry and Auvergne - where even the Duke's nominal suzerainty was at times doubtful.• He did not ask for independence and never attempted to repudiate the suzerainty of the sultan.Origin suzerainty (1800-1900) French suzerainté, from an unrecorded Old French suserain “ruler”, from sus “up” + -erain (as in soverain “sovereign”)