Son of Ar-Abattârik and the 20th ruler of Númenor, whose Quenya name was Herunúmen. In both languages, his name (somewhat heretically) means “Lord of the West” (LotR/1036, S/267). Its first element adûn means “west”, which implies that its second element means “lord”, but it isn’t clear whether this element is *akhôr or *khôr. I think that khôr is more likely, because it resembles the Primitive Elvish root √KHER “rule, govern, possess”, to which it may be related.