Primitive elvish
day
root. *great
day
root. *great
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
ƀele Reconstructed
root. *great
The root √DAY appeared in Definitive Linguistic Notes (DLN) from 1959 beside √NDAY “dreadful, abominable, detestable”, possibly having that same meaning (PE17/151). In this note Tolkien said that in Quenya √DAY was not used, and that the strengthened form √NDAY was in Quenya blended with √NAY “cause bitter pain, grief”.
I suspect that the “dreadful” meaning applied only to the strengthened form √NDAY, since the unstrengthened form √DAY is the basis for the adjective ✶daira > S. daer “great, large”, where Tolkien reiterates that the root √DAY was not used in Quenya (VT42/11). In the sense “great”, √DAY may have been a restoration of the rejected root ᴹ√DAƷ “great” from The Etymologies of the 1930s (EtyAC/DAƷ).
Whether √DAY meant “great” or “dreadful”, it seems to have replaced another root from The Etymologies of the 1930s: ᴹ√DAY “shadow” (Ety/DAY). The Noldorin word N. dae “shadow” was an element in the 1930s names Daedhelos “Shadow of Fear” and Dor-Daideloth “Land of the Shadow of Dread” (LR/405). But in the aforementioned 1959 note, Tolkien derived S. daedelos from √NDAY and translated it as “horrible fear” (PE17/151), consistent with the Sindarin name for Mirkwood: Taur e-Ndaedelos “Forest of the Great Fear” (LotR/1134). Likewise in later versions of the Silmarillion, S. Dor Daedeloth was translated “Land of Great Dread” (WJ/183) with no mention of “shadow”. Thus it seems ᴹ√DAY “shadow” was abandoned.