Gwillym moelelo wa lebitso le letle: Ela hloko, Mehleng ea kajeno, Bōpo, E fokolang, E thabileng. Fumana Gwillym moelelo oa lebitso.
Kiser lebitso la motumo o motle ka ho fetisisa: Ela hloko, Bōpo, E fanang ka, Lehlohonolo, Mehleng ea kajeno. Fumana Kiser se boleloang ke lebitso.
Gwillym tšimoloho ea lebitso la pele. Welsh form of William. Fumana Gwillym tšimoloho ea lebitso la pele.
Gwillym lebitso la diminuti: Gwil. Fumana Mabitso a marang-rang a Gwillym.
Mabitso a sa tšoaneng bakeng sa Gwillym linaheng le lipuo tse sa tšoaneng: Bill, Billie, Billy, Guglielmo, Guilherme, Guillaume, Guillem, Guillermo, Gwilherm, Illiam, Jami, Jelle, Liam, Pim, Uilleag, Uilleam, Uilliam, Ulick, Vilĉjo, Vilém, Vilhelm, Vilhelmas, Vilhelmi, Vilhelmo, Vilhelms, Vilhjálmur, Vilho, Vili, Viliam, Vilim, Vilis, Viljami, Viljem, Viljo, Vilko, Ville, Villem, Vilmos, Wil, Wilhelm, Wilhelmus, Wilkin, Wilky, Will, Willahelm, Willem, Willi, William, Willie, Willy, Wilmot, Wim, Wiremu, Wöllem, Wullem, Wum. Fumana Gwillym ka lipuo tse ling.
Mabitso a tloaelehileng ka lebitso la ho qetela Kiser: Darlena, Lyla, Anette, Marlyn, William. Fumana Mabitso a tsamaeang le Kiser.
Ho lumellana ha Gwillym le Kiser ke 83%. Fumana Tšebelisano ea Gwillym le Kiser.