Þingdalsvatnnafnorð hvorugkyn · ÖrnefniFallbeygingarEt.eintalaFt.fleirtalaEintalaNf.nefnifallÞingdalsvatnÞf.þolfallÞingdalsvatnÞgf.þágufallÞingdalsvatniEf.eignarfallÞingdalsvatns