A noun meaning “wind” derived from the root ᴹ√WAW(A) (Ety/WĀ). Here the [[ilk|initial [w] became [gw]]], and after the final vowel vanished, the [[ilk|final [w] became [u]]].
Doriathrin
gwath
noun. shade
gwau
noun. wind
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 noun glossed “shade” (shadow) derived from the root ᴹ√WATH (Ety/WATH). It is a clear example of how [[ilk|initial [w] became [gw]]] in Ilkorin, and it appears in several names: Thuringwethil “(Woman of) Secret Shadow” and Urthin Gwethion (unglossed but presumably “✱Mountains of Shadow”).