What is the meaning of the name Erin?

The name Erin is an extremely old one that has long been associated with Ireland ('Erin go bragh' means 'Ireland forever'). Legend has it that Erin (or Eire) was one of three goddesses who represented peace, love and joy. Her sisters, Fodla and Banba, represented hope and love respectively, leaving Erin with peace. Therefore, one meaning of the name Erin is 'peace'.
Technically, though, Erin is though to come from the Irish Gaelic word Eireann, which means either 'of Ireland' or simply 'Ireland'.