A region on the coast of Beleriand (S/244). Tolkien indicated that the name meant “(the land) beside the Verna” (PE17/19, 71), with its initial element ar- “beside” and its middle element being the (otherwise unknown) place Verna. Its final element -ien is seen in the names of other lands, such as Hildórien and Lórien.
Conceptual Development: The name ᴹQ. Arvernien first appeared in Lord of the Rings drafts from the 1940s (TI/99) as a place where Eärendil tarried before questing for Valinor, described in Bilbo’s “Song of Eärendil” as recited in Rivendell (LotR/233). It was added to Silmarillion maps and narratives later (WJ/184).
Arvernien place-name, "(the land) beside the Verna" (PE17:19). It is unclear what "Verna" refers to.