A city in western Númenor, “so called because it faced the sunset” (S/261). It is andúnë “sunset” with the abstract-noun suffix -ië.
Conceptual Development: The name ᴹQ. Andúnie appeared in the earliest tales of Númenor, first as a name for Númenor itself (LR/14), but soon changing to the name of a major city of that land (LR/25). At one point Tolkien considered changing this name to ᴹQ. Undúnië, but he soon rejected the idea (SD/333, SD/340 note #2).
Andúnië (apparently a variant form of andúnë) place-name, a city and port on the western coast of Númenor, said to mean "sunset". (Appendix A, Silm, UT:166, NDŪ/VT45:38)