A negated form of fárea “enough” (LR/72).
Qenya
fárea
adjective. enough, sufficient
ufárea
adjective. not enough
faren
adverb. enough
ananta úva táre fárea, ufárea
but yet it will not be enough, not enough
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 word appearing as farea “enough, sufficient” in The Etymologies of the 1930s glossed under the root ᴹ√PHAR “reach, go all the way, suffice” (Ety/PHAR). Ink revisions changed the form to fā̆rea (EtyAC/PHAR). In the poem Fíriel’s Song from around this same time, Tolkien had fárea “enough” in the phrase ananta úva táre fárea, ufárea “but yet it will not be enough, not enough” (LR/72).