A root in The Etymologies of the 1930s glossed “sick” with derivatives ᴹQ. engwa/N. gem “sickly” (Ety/GENG-WĀ). It was given as ᴹ√GENG-WĀ, and thus represented an extension of an otherwise unattested root ᴹ√GENG. In the entry for ᴹ√YEN from The Etymologies it appeared as ᴹ√GEM in the discussion of N. ingem “old, (lit.) year-sick” (EtyAC/YEN), but I believe this represents the Noldorin phonetic developments of the true primitive form rather than a conceptual variation. The continued appearance of Q. Engwar in The Silmarillion narratives of the 1950s and 60s hints that this root may have remained valid as well.
Middle Primitive Elvish
wā
root. blow
wān
noun. goose
waiwa
root. blow
wanōrō
noun. one of kin
waw
root. blow
kwam
root. *sick
gengwa
root. sick
kaltwa
?. [unglossed]
alkwā
noun. swan
maiga
root. [unglossed]
An unglossed root appearing in the first version of Tengwesta Qenderinwa from the 1930s (TQ1) to illustrate certain patterns of root formation (PE18/66). It may have serving as the basis for ᴹQ. Maia, though this word was given different derivations later.
wo
root. together
bay
root. [unglossed]
laikwā
adjective. fresh
aikwā
adjective. tall, steep
auluta-
verb. [unglossed]
gem
root. *sick
geng
root. *sick
iw
root. [unglossed], [ᴱ√] *fish
khlip
root. [unglossed]
An unglossed root in a rejected paragraph from the Quenya Verbal System (QVS) written in 1948 (PE22/112 note #78).
kōmā
noun. [unglossed]
morókō
noun. bear
phan
root. [unglossed]
A deleted root in The Etymologies of the 1930s with no glosses or derivatives and no clear function (EtyAC/PHAN).
skil
root. [unglossed]
A root mentioned in passing in as a variant of ᴹ√KIL “divide” in The Etymologies of the 1930s, but it had no derivatives and appeared nowhere else (Ety/KIL).
stin
root. [unglossed]
stā
root. [unglossed]
torōmā
noun. [unglossed]
tundā
adjective. tall
uruk
root. [unglossed]
A root in The Etymologies of the 1930s with no glosses or derivatives and no clear function (EtyAC/URUK).
us
root. [unglossed]
A root in The Etymologies of the 1930s with no glosses or derivatives and no clear function (EtyAC/US).
wō̆-
prefix. together
A root connected to sickness, first appearing as ᴱ√QAMA from the Qenya Lexicon of the 1910s with derivatives like ᴱQ. qáme “sickness, nausea”, ᴱQ. qama- “to be ill, vomit”, G. cwam “ill”, and G. côma “disease, illness” (QL/76; GL/26, 28). It reappeared in The Etymologies of the 1930s as ᴹ√KWAM with derivatives ᴹQ. qáme, N. paw and Ilk. côm “sickness” (Ety/KWAM). It does not appear again in Tolkien’s later writing, but there is nothing contradicting its validity either.