Entry 1 sense Webster, 1913 Whosesoever /(-sō̇*ĕv"ẽr)/ · Whose·so·ev·er · IPA /ˌhuzsoʊˈɛvəɹ/ 01 pron. The possessive of whosoever. See Whosoever. 1. The possessive of whosoever. See Whosoever. See: Whosoever