Ertha \e-rtha, er-tha\ as a girl's name is a variant of Eartha (Old English) and Hertha (Old English), and the meaning of Ertha is "Earth". The baby name Ertha sounds like Artha, Aretha, Oretha, Erda and Orthia. Other similar baby names are Eltha and Etha. View a list of the 2 names that reference Ertha.