A noun appearing as N. rhîf in The Etymologies of the 1930s under the root ᴹ√RĪ (Ety/RĪ). Christopher Tolkien did not give this word a gloss in The Etymologies as published in The Lost Road, and many people assumed it had the same meaning as its Quenya equivalent ᴹQ. ríma “edge, hem, border” (LR/358), but Carl Hostetter and Patrick Wynne indicated it had a separate gloss “brink, brim” in their Addenda and Corrigenda to the Etymologies (VT46/11). Hostetter and Wynne also indicated Tolkien considered changing the root: “Alter to SRI-”.

Neo-Sindarin: Based on David Salo’s theory that final v became w after i (GS/§4.173, GS/§4.174), some Neo-Sindarin writers adapt this Noldorin word as ᴺS. rîw, with the usual adjustment of Noldorin rh to Sindarin r (GS/283, HSD/rîw). However, I think the bulk of the evidence is that v > w was limited to diphthongs ae and oe in Sindarin. Also, given the revision of the root to SRI, I’d just keep the Noldorin form ᴺS. rhîf “brink, brim” for purposes of Neo-Sindarin.

Conceptual Development: The Gnomish Lexicon of the 1910s had G. raim “edge, border-line” derived from the early root ᴱ√rib “a rim” (GL/64), a root that was ᴱ√RIMI in the contemporaneous Qenya Lexicon (QL/80).