Jowan kacha mma aha pụtara: Kechioma, Okike, Oge a, Enyi na enyi, Iwe. Nweta Jowan pụtara aha.
Trefz kacha mma aha nna pụtara: Oge a, Obodo, Enyịn, Okike, Enyi na enyi. Nweta Trefz pụtara aha nna.
Jowan si malite aha mbụ. Cornish form of John. Nweta Jowan si malite aha mbụ.
Agakọta aha maka Jowan na mba dị iche iche na-asụ asụsụ: Anže, Deshaun, Deshawn, Ean, Eoin, Evan, Ganix, Ghjuvan, Gian, Gianni, Giannino, Giannis, Giovanni, Gjon, Hampus, Hank, Hanke, Hankin, Hann, Hanne, Hannes, Hannu, Hans, Hasse, Honza, Hovhannes, Hovik, Hovo, Iain, Ian, Iancu, Ianto, Iefan, Ieuan, Ifan, Ioan, Ioane, Ioann, Ioannes, Ioannis, Iohannes, Ion, Ionel, Ionuț, Iván, Ivan, Ivane, Ivano, Ivica, Ivo, Iwan, Jaan, Jānis, Jack, Jackin, Jake, Ján, Jancsi, Janek, Janez, Jani, Janika, Jankin, Janko, Janne, Jannick, Jannik, Jan, Jan, János, Janusz, Jean, Jeannot, Jehan, Jehohanan, Jens, Jo, João, Joannes, Joan, Joãozinho, Joĉjo, Johan, Johanan, Johann, Johannes, Johano, John, Johnie, Johnnie, Johnny, Jón, Jonas, Jone, Joni, Jon, Jon, Jóannes, Jóhann, Jóhannes, Joop, Jouni, Jovan, Juan, Juanito, Juha, Juhán, Juhan, Juhana, Juhani, Juho, Jukka, Jussi, Keoni, Keshaun, Keshawn, Nelu, Nino, Ohannes, Rashaun, Rashawn, Seán, Sean, Shane, Shaun, Shawn, Shayne, Siôn, Sjang, Sjeng, Van, Vanja, Vanni, Vano, Vanya, Xoán, Xuan, Yahya, Yan, Yanick, Yanko, Yann, Yanni, Yannic, Yannick, Yannis, Yehochanan, Yianni, Yiannis, Yoan, Yochanan, Yohanes, Yuhanna, Zuan, Žan. Nweta Jowan na ndị ọzọ asụsụ.
Kasị nkịtị aha na aha ikpeazụ Trefz: Coral, Forrest, Aleida, Casandra, Sonia. Nweta Aha na-aga na Trefz.
Ndakọrịta nke Jowan na Trefz bụ 78%. Nweta Ndakọrịta nke Jowan na Trefz.