Irildë fem. name "Idhril" (Idril) (LT2:343), #Írildë (J.R.R. Tolkien: Artist & Illustrator p. 193), Írildë also as name of a Númenorean woman (UT:210). Irildë Taltyelemna = (later) Sindarin Idril Celebrindal;replaced Irildë Taltelepsa (KYELEP/TELEP; Taltelemna in the Etymologies as printed in LR is an error for Taltyelemna, VT45:25). Tolkien seems to have replaced Irildë as the Quenya form of Idril with Itaril, Itarillë, Itarildë, q.v., in which case the Sindarin form is definitely Idril and not Idhril.
Quenya
taltea
adjective. insecure
talta-
slip, slide down, collapse, slope
talta-
verb. to slip, slide down, fall, to slip, slide down, collapse, fall, [ᴹQ.] slip down, slope
talta-
verb. slip, fall
Irildë
idhril
tál
noun. foot, foot; [ᴹQ.] bottom, [ᴱQ.] lowest part
The Quenya word for “foot” derived from the root √TAL of similar meaning (PE19/103; VT49/17; Ety/TAL). Given its Sindarin cognate S. tâl (not ✱✱taul) its ancient stem form must have had a short vowel, with the long vowel in the uninflected form the result of the subjective noun case which lengthened the base vowel of monosyllables (PE21/76). Q. tál could also refer to the bottom of things (PE21/21, 76) analogous to English “foot of the mountain” and similar phrases.
Conceptual Development: The earliest iteration of this word was ᴱQ. tala “foot” in the Qenya Lexicon of the 1910s under the early root ᴱ√TALA “support” (QL/88), a form also appearing in the contemporaneous Poetic and Mythological Words of Eldarissa (PME/88). In the Early Qenya Grammar of the 1920s it became ᴱQ. tál with plural tăli indicating an ancient short vowel (PE14/43, 76). In the Declension of Nouns from the early 1930s, ᴹQ. tāl had inflected forms with tal-, again indicating a short vowel in the stem (PE21/21), and likewise with the (1930s-style) genitive form talen in The Etymologies written around 1937 (Ety/TAL). Most of its later appearances also imply a short vowel in the stem, the main exception being the plural form táli in the 1950s version of the Nieninquë “poem”.
undu
down, under, beneath
undu adv. (and prep.?) "down, under, beneath" (UNU, VT46:20); prefixundu- "down", in undulávë "down-licked" = covered. (Nam)
undu
down
talta- vb. "slip, slide down, collapse, slope" (TALÁT); reduplicated stem in the participle talta-taltala in Markirya, simply translated "falling" in MC:215. Strong intransitive conjugation: present talta, aorist talt- [derived from talati > talti, hence presumably *talti*- with endings and taltë without any], past talantë, perfect ataltië. Weak transitive conjugation: present taltëa, aorist talta, past taltanë**. This is said to be the conjugation type of a certain class of verbs, namely "√TALAT stems" (PE17:186).