Quendi

Quendi (Q, pron. [ˈkʷendi], singular Quendë, pron. [ˈkʷende], though the plural form was more common), was the name given by the Elves to their own kind while they still dwelt at Cuiviénen. It is commonly said to mean "speakers; those who speak with voices", being from a time when the Elves had not yet encountered other beings capable of speech.

Quendë is the Quenya form of the word, in Primitive Quendian the word had been kwendē̆. There it derives from the root KWENED-, an elaboration of KWEN-, a root for “person”.
Although this root has no direct derivatives that are connected to language, it is probable related to the root KWE- "vocal speech".

After the Sundering of the Elves, the Quenya word had been replaced by Elda in common usage but it remained in use as a technical term distinguishing the Elves from the Ainur and in the context of lore.
In Telerin and Sindarin the word fell out of use after the sound change kw > p due to collisions with the roots PEN- "to lack" and PED- "slope, slant down". In Quenya it became