The kingdom of the witch king (LotR/146). In the manuscript for Tolkien’s Nomenclature of the Lord of the Rings, he explained that it was corrupted Elvish: the pure Sindarin form of the name would be Angbar, and the pure Quenya form would be Angamar (RC/20). It is perhaps a combination of S. ang “iron” and Q. már “home”, hence: “✱Iron Home”.
Conceptual Development: In Lord of the Rings drafts from the 1940s, this name first appeared as N. Angmar (WR/334).
ang (“iron”) + (m-)bar (“land, dwelling”) The lenition of the second element is unclear (we would rather expect Angbar) but edain often made mistakes when giving places Elvish names; see VT42 “Rivers and Beacon-hills”).