An adjective for “grey” derived from primitive ᴹ✶thindi (Ety/THIN) because primitive final vowels vanished in Ilkorin.
Doriathrin
hedhu
adjective. grey
thind
adjective. grey
There are more words but they are from Tolkien's earlier conceptional periods. Tolkien likely changed these words as he evolved the aesthetics and completeness of the languages. You may even find languages that Tolkien later rejected. Do not mix words from different time periods unless you are familiar with the phonetic developments.
Below: Tolkien's Late Period (1950–1973). These are from Tolkien's late conceptual period — his most settled forms of the languages. Prefer these over the earlier ones above when composing new text.
A Doriathrin adjective for “grey” written heðu in The Etymologies, and derived from the primitive form ᴹ✶khithwa [kʰitʰwa] (Ety/KHIS). This word illustrates several interesting phonetic changes in Ilkorin.
The [[ilk|[i] became [e] before the final [a]]].
Both the aspirates became voiceless spirants: [kʰ-] > [x-] and [-tʰ-] > [-θ-].
Later the [[ilk|initial [x-] became [h-]]].
Meanwhile the [[ilk|medial [-θ-] voiced to [-ð-]]] (“dh”).
The [[ilk|primitive final [a] was lost]].
Afterwards, the resulting [[ilk|final [w] became [u]]].
In most other Doriathrin words, a [[ilk|final [u] from [w] further developed into [o]]]; it is unclear why this change did not occur here.