Willo m. Old High German willo 'will', or a pet form of any of various names beginning with this element.

Austria

Latin

◑ 1124 Willinc (nom) UrkStyria 110

Estonia

Middle Low German

◑ 1428 Wyllyngh BbRT p. 353

France

Latin

◑ c823 Willonus (nom) irminon-vol2 86, Ved; 1121 Guilenci (gen) clairvaux-12thc 1; 1125x1136 Guilenci (gen) CartYonne1 CXXXIX, Guilencus (nom) ibid. CXXXIX; 1131 Wilenco (abl) clairvaux-12thc 4; 1135 Wilenci (gen) ibid. 7, Wilenco (abl) ibid. 7, Wilencus (nom) ibid. 7; 1147 Wilenci (gen) ibid. 15, Wilenco (abl) ibid. 17, Wilencus (nom) ibid. 18; 1147x1162 Wilencus (nom) ibid. 52, Willencus (nom) ibid. 52; 1155 Wilenchi (gen) ibid. 30; 1159 Wilenchi (gen) ibid. 36, Wilencus (nom) ibid. 36; 1163 Wilenco (abl) ibid. 99; 1163–64 Vilencus (nom) ibid. 106; 1164 Vilencus (nom) ibid. 120; 1172 Guilenchi (gen) ibid. 150; 1219 Villenc (nom) CartAub

Middle French

● 1386 Guillo MemBret-II col. 513

Germany

Latin

● 963x1023 Willo (nom) TradCorb §226; 987 Willo (nom) HambUrk-vol1 XLVIII

Switzerland

Latin

◑ 1163 Willincus (nom) CartHaut 13