Noldorin 

thlein

adjective. lean, thin, meagre

The Etymologies of the 1930s had N. {thlîn >>} thlein derived from ᴹ✶slinyā “lean, thin, meagre” under the root ᴹ√SLIN (Ety/SLIN) with the initial sl becoming thl as was generally the case in Noldorin of the 1930s.

Neo-Sindarin: In Sindarin of the 1950s and 60s, initial sl became voiceless lh and ei became ai in final syllables, so I would adapt this word as ᴺS. lhain as suggested in HSD (HSD).

Noldorin [Ety/SLIN; EtyAC/SLIN] Group: Eldamo. Published by

thlein

adjective. lean, thin, meagre

Noldorin [Ety/386, X/LH] Group: SINDICT. Published by