Gwillym kacha mma aha pụtara: Enyịn, Oge a, Okike, Obodo, Eji obi ụtọ. Nweta Gwillym pụtara aha.
Penning kacha mma aha nna pụtara: Enyi na enyi, Emesapụ aka, Oké njọ, Okike, Eji obi ụtọ. Nweta Penning pụtara aha nna.
Gwillym si malite aha mbụ. Welsh form of William. Nweta Gwillym si malite aha mbụ.
Gwillym aha diminutives: Gwil. Nweta Nicknames maka Gwillym.
Agakọta aha maka Gwillym na mba dị iche iche na-asụ asụsụ: 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. Nweta Gwillym na ndị ọzọ asụsụ.
Kasị nkịtị aha na aha ikpeazụ Penning: Kathy, William, Byron, Laura, Beryl. Nweta Aha na-aga na Penning.
Ndakọrịta nke Gwillym na Penning bụ 71%. Nweta Ndakọrịta nke Gwillym na Penning.