Eastemnet
From Tolkien Gateway
The wide land between the Rivers Entwash and Anduin, the easternmost of those held by the Rohirrim. There were few fixed settlements here, but many of the herdsmen of the Rohirrim lived a nomadic existence on the fields of the Eastemnet, living out of temporary camps and driving their herds across the grasslands.
See also
Etymology
Emnet means "plain"