topon. Rivendell, (lit.) Deep Dale of the Cleft
Sindarin name of Rivendell (LotR/657), a combination of imlad “deep valley” and riss “cleft” (PE17/87), so literally “Deep Dale of the Cleft” (RC/482).
Conceptual Development: In Lord of the Rings drafts from the 1940s, this name first appeared as N. Imlad-ril (rejected) >> Imladrist (TI/120), but was soon revised to Imladris (TI/146), a form that also appeared in the Etymologies with essentially the same derivation as given above (Ety/RIS²).