The normal Sindarin word for “wind”, usually appearing as gwae but sometimes as gwaew, most frequently derived from √WAY “blow” but also a bewildering variety of other roots (NM/237; PE17/33-34, 189); see the entry for √WĀ for further discussion.
Conceptual Development: The earliest form of this word was G. gwâ “wind” from both Gnomish Grammar and Gnomish Lexicon from the 1910s (GG/14; GL/43). The form ᴱN. gwá “wind” reappeared in Early Noldorin Word-lists from the 1920s (MC/217), but in the Nebrachar poem from circa 1930 the form was gwaew “wind” (MC/217). It was N. gwaew “wind” in The Etymologies of the 1930s from the root ᴹ√WAIWA (Ety/WĀ), and appeared a number of times in later writings as both gwae and (more rarely) gwaew, as noted above.
Neo-Sindarin: For purposes of Neo-Sindarin, I prefer using only gwae for “wind”, reserving gwaew for “storm”.
A word appearing in the rejected name Côf Gwaeren Bel “Windy Bay of Bel” (VT42/15), an adjectival form of gwae “wind”. Despite this rejection, I think ᴺS. gwaeren “windy” is perfectly viable for purposes of Neo-Sindarin.
Conceptual Development: A likely precursor is G. {gwavwed >> gwanwed >>} gwavwed “windy” from the Gnomish Lexicon of the 1910s, an adjectival form of G. gwâ “wind” (GL/43).