A noun in the Quendi and Eldar essay from 1959-60 glossed “frost-patterns” (WJ/417). It also appeared in some etymological notes from around 1959 with the stem forms niquiss- or niquits-, where it was derived from the root √NIK(W) (PE17/168). In those 1959 notes it was glossed “ice-flake or snowflake — also petal (loose) of a white flower”. In both documents, it had a variant form niquessë of similar meaning, where the second element was modified by association with quessë “feather”, thus literally “chill feather” (WJ/417; PE17/168).
Conceptual Development: The Qenya Lexicon of the 1910s had ᴱQ. niqis (niqiss-) “snow” under the early root ᴱ√NIQI “white” (QL/66).
Neo-Quenya: For purposes of Neo-Quenya, I’d mostly use niquis(s-) for “snowflake” or “ice-flake”, and metaphorically for the loose petal of a white flower. I’d use the variant niquessë for “frost pattern” and more loosely for “snowflake”. For “frost” itself I’d use nixë. This is mainly to help differentiate these otherwise very similar words.
niquis noun "frost-patterns; ice-flake or snowflake also petal (loose) of a white flower" (stem niquits- or niquiss-), also niquessë by association with quessë "feather" (WJ:417, PE17:168). In early "Qenya", the gloss was simply "snow" (LT1:266).