Noldorin rhî is a descendant form of Old Noldorin ríge, deriving from root RIG.
Noldorin
rhî
noun. crown
rhî
noun. crown, wreath, garland
rhîn
adjective. crowned
rhîs
noun. queen
rhîf
noun. brink, brim
rhîf
noun. edge, hem, border
rhîn
noun/adjective. crowned
rhîn
noun/adjective. crowned lady, queen
rhîs
noun. queen
rhien
noun/adjective. crowned
rhien
noun/adjective. crowned lady, queen
rhíw
noun. winter
rhain
noun. border
rhain
noun. border
rhein
noun. border
rhî
rhî
bereth
noun. queen, spouse
bereth
noun. queen
edrein
noun. border
An adjective appearing as N. rhîn “crowned” in The Etymologies of the 1930s under the root ᴹ√RIG (Ety/RIG). The long î is probably the result of the vocalization of g before nasal n, from primitive adjective ✱rignā.
Neo-Sindarin: Since initial r unvoiced to rh in Noldorin of the 1930s but not in Sindarin of the 1950s and 60s, most Neo-Sindarin writers adapt this word as ᴺS. rîn “crowned”, as suggested in HSD (HSD).