 The modern English word Earth developed from a wide variety of Middle English forms , which derived from an Old English noun most often spelled eorðe . It has cognates in every Germanic language , and their proto @-@ Germanic root has been reconstructed as * <unk> . In its earliest appearances , eorðe was already being used to translate the many senses of Latin terra and Greek <unk> ( gē ) : the ground , its soil , dry land , the human world , the surface of the world ( including the sea ) , and the globe itself . As with Terra and Gaia , Earth was a personified goddess in Germanic paganism : the Angles were listed by Tacitus as among the devotees of Nerthus , and later Norse mythology included Jörð , a giantess often given as the mother of Thor . 
