Early Primitive Elvish
kṇřṇ
root. shine
kṇðṇ
root. shine
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 root in the Qenya Lexicon of the 1910s given as ᴱ√KṆŘṆ “shine” with derivatives in both Qenya and Gnomish, such as ᴱQ. kanda- “blaze”, G. cintha- “to light, set alight”, ᴱQ. kanwa “lurid”, and G. cantha “flame” (QL/47; GL/25-26). It may be a variant of ᴱ√KṚN “✱red” (QL/48). There are no signs of this root in Tolkien’s later writing.