A noun appearing as cwathli “plume, spray, tassel” in the Gnomish Lexicon of the 1910s, related to G. cwas- “wag, shake, flap” (GL/28) and thus almost certainly derived from the early root ᴱ√QASA which likewise was the basis for “shake” and “plume” words (QL/76). It appeared as cwathil “a plume” on a different page of the Gnomish Lexicon (GL/28).
Quenya
lúpe
noun. plume
A noun for “plume” from notes on Qenya Spelling from the 1930s, descriptive of a curved tehta sign but probably inspired by (and still applicable to) the plume feather of a bird (PE22/63).