The most common Quenya word for “leg” (PE17/122), also used of the “stem” of a tengwar symbol (LotR/1118) and probably the stem of plants as well. Based on the verb telconta-, its noun stem is telco- and hence it is probably derived from primitive ✱telekō, an elaboration of the root ᴹ√TELEK (Ety/TÉLEK). In The Etymologies of the 1930s it had an “analogical plural” telqui; such plurals generally appear with noun stems ending in cu- such as urqui plural of urco (urcu-). However, since the plural of telco was “analogical” it is clear that Tolkien intended its plural to be borrowed from other similar nouns rather than being the result of its historical phonological development. Whether this was true only for the plural or for other nouns cases as well is unclear.
Conceptual Development: The earliest iteration of this word was ᴱQ. pelko (pelko-) “leg” in the Qenya Lexicon of the 1910s under the early root ᴱ√PELE that was also the basis for “pivot” words (QL/73). This word reappeared in the Early Qenya Grammar and English-Qenya Dictionary of the 1920s, with plural form pelqi, perhaps adapted from its (Early Qenya) dual which was also pelqi (PE14/76; PE15/74). However, noun declensions from the late 1920s had ᴱQ. telko with the gloss “stem” (PE16/112-113).
This late 1920s ᴱQ. telko “stem” may initially have been a distinct word, since ᴹQ. pelko “leg” appeared in declensions from the early 1930s (PE21/48-49), but in a slightly later declension telko was glossed “leg” (PE21/53), and in the Declension of Nouns, telko was glossed “stem, leg” as an example of -u̯ǝ nouns (PE21/12). ᴹQ. telko was “leg” in The Etymologies written around the 1937, and Tolkien seems to have stuck with it thereafter (Ety/TÉLEK). Furthermore, in notes on The Feanorian Alphabet from the 1930s and 40s, telko was glossed “stem” as both the stem of a tengwar symbol and the name of vowel carriers: (short) telko ` and (long) anda-telko ~ (PE22/20, 22, 51).
Neo-Quenya: For purposes of Neo-Quenya, I assume that telco “leg; stem” has aligned with the noun class of [ᴹQ.] ranco (rancu-) “arm” for all noun cases.
telco noun "stem" of a Tengwa symbol (Appendix E). The Etymologies gives telco ("k") pl. telqui ("q") "leg" (the pl. form is said to be analogical) (TÉLEK). It seems, then, that the word can refer to a "stem" or "leg" in general as well as the stem of a Tengwa. In the pre-classical Tengwar system presupposed in the Etymologies, telco is used to refer to a carrier symbol (VT46:18, 33)