kwal
root. die, pain, die, pain, [ᴹ√] die in pain
qual-
verb. to die
A verb for “to die” in Late Notes on Verb Structure (LVS) from 1969 (PE22/152), clearly based on the root √KWAL having to do with pain and death (PE18/91, 103; Ety/KWAL). As such, I would use this verb for undesirable or painful death, as opposed to fir- “to die (a natural or peaceful death)”.
Conceptual Development: ᴱQ. qal- meant “die” in Early Qenya Word-lists of the 1920s (PE16/134), and the root √KWAL had a long history of connection to death and pain in Tolkien’s writings.
fir-
die, fade
fir- vb. "die, fade" (cf. fifíru-); aorist (?) fírë "expire"; augmentless perfect fírië, translated "she has breathed forth"(but no explicit element meaning "she" seems to be present) (MR:250, 470, VT43:34)
qual-
verb. die
fir
die
1) fir- (i fîr, i firir) (fade), 2) gwanna- (i **wanna, in gwannar**) (depart)
fir
die
(i fîr, i firir) (fade)
gwanna
die
(i ’wanna, in gwannar) (depart)
Beware, older languages below! The languages below were invented during Tolkien's earlier period and should be used with caution. Remember to never, ever mix words from different languages!
kwal
root. die (in pain)
gor-
verb. to die
gurdh-
verb. to die
A verb for “die” in Early Noldorin Grammar of the 1920s with present form gwardh indicating vowel gradation (PE13/132), so that it was likely based on the early root ᴱ√GWṚÐṚ (QL/104) with a/u variations due to the different developments of long syllabic ṝ vs short ṛ.
Conceptual Development: The verb G. gor-“die” appeared in the Gnomish Lexicon of the 1910s related to gurthu “death” (GL/41, 43), thus also based on the early root ᴱ√GWṚÐṚ (QL/104).
Neo-Sindarin: S. gurth “death” survived in Tolkien’s later writings, so in theory the Gnomish verb gor- could be salvaged as a derivative of the later root √ÑGUR “die”. However, gor- already serves various functions in Sindarin, so I’d stick with the later verbs fir- and [N.] gwanna- for “to die”.
gwṛðṛ
root. die
qala
root. die
qal-
verb. to die
This root was connected to death and pain through Tolkien’s life. Its first appearance was as ᴱ√QALA “die” from the Qenya Lexicon of the 1910s, with derivatives like ᴱQ. qalin “dead, dying” and ᴱQ. qalme “death” (QL/76). The latter appeared as ᴱQ. qalme “agony” in word lists from the 1920s (PE16/144). In The Etymologies of the 1930s Tolkien gave the root as ᴹ√KWAL “die (in pain)”, again with ᴹQ. qalin “dead” and ᴹQ. qalme “agony, death” among other derivatives (Ety/KWAL).
The root appeared in both versions of the Tengwesta Qenderinwa from the 1930s (TQ1) and circa 1950 (TQ2) with the glosses “die” (TQ1: PE18/42, 58, 65; TQ2: PE18/103) and “pain” (TQ2: PE18/91). In TQ2 Tolkien connected it to similar roots √GWAL “suffer torment” and √KWEL “fade, die away, grow faint” (PE18/103). Somewhat interestingly, Tolkien gave almost no Sindarin or Noldorin derivatives of this root, indicating it probably fell out of use, most likely crowded out by derivatives of √PAL.