In Irish mythology, Elcmar (also Ecmar, Elcmhaire) was the husband of Boann. The Mythology of pre-Christian Ireland did not entirely survive the conversion to Christianity, but much of it was preserved shorn of its religious meanings Boann (or Boand) is the Irish mythology goddess of the River Boyne, a river in Leinster, Ireland. He may be Nuada under another name.