A very well attested adjective for “full, filled” derived from the root √KWAT “fill” (PE17/68; PE23/101; Ety/KWAT).
Conceptual Development: The Qenya Lexicon of the 1910s ᴱQ. qanta “full” derived from the early root ᴱ√QṆTṆ (QL/78). The contemporaneous Qenya Phonology had a variant ᴱQ. cunta “full” with a different vocalization of ṇ; in that document qanta was glossed “whole, all” (PE12/11). In QL, there was a similar form i qanda that meant “all the, the whole” in combination with the definite article (QL/70). The word qanta was glossed “all” Qenya word-lists of the 1920s (PE16/142), and prefixal qa(qe)- meant “all, every” in Demonstrative, Relative, and Correlative Stems (DRC) from 1948 (PE23/101). In Tolkien’s later writings usually √IL meant “all”.
quanta (1) ("q") adj. "full" (KWAT, Narqelion, VT39:8, VT43:28), "filled, full" (PE17:68); the gloss "filled" would suggest that quanta can be regarded as a passive participle of quat- (q.v.) In these phrases: quanta sarmë "full writing", writing with separate letters for vowels (VT39:8); #quanta tengwë "full sign" (only pl. quantë tengwi is attested), in early Elvish analysis of Quenya the term for a consonant + a vowel (then analyzed as a kind of unitary phoneme rather than two phonemes); hence a stem like mata- "eat" was analyzed as two quantë tengwi, namely ma + ta. (VT39:5)