A root in The Etymologies of the 1930s glossed “feel disgust at, abhor” with derivatives ᴹQ. feuya- and N. fuia- of the same meaning (Ety/PHEW).
Middle Primitive Elvish
ata
root. father
atar
noun. father
atū
noun. father
atta
root. two
atta
cardinal. two
atyēnar
noun. anniversary day
atat
root. again, back
asat
root. *dust
tata
root. two
kanat
root. four
kalat
noun. light
yē
preposition. at
phew
root. feel disgust at, abhor
khaw
root. rest, lie at ease
mardasē
adverb. at home
ramna
noun. wing (horn), extended point at side
ken
root. see, perceive, look at, observe, direct gaze
kyen
root. see, perceive, look at, observe, direct gaze
-d
suffix. allative
lop
root. horse, [ᴱ√] *run (of animals), gallop, lope; [ᴹ√] horse
This root was the basis for horse words starting with the Qenya Lexicon of the 1910s, where it appeared unglossed as ᴱ√LOPO (QL/56). It was compared to the root ᴱ√LOQO, and these roots include the verbs ᴱQ. lopo- “gallop, run (of animals)” and ᴱQ. loqo- “run (of human beings)”, and I think it likely that those were also the meanings of the roots (QL/56). In the Qenya Lexicon, ᴱ√LOPO had the derivatives ᴱQ. lōpa “horse or mare” and ᴱQ. lopsi “mare” (QL/56), but elsewhere in that document there was the word ᴱQ. lapatte “rabbit” < ᴱ✶lopatte, so I think that word is related as well, though Tolkien did mark the primitive form with a “?” (QL/51). The probably-related word ᴹQ. lopo “rabbit” appeared in a discussion of nouns from the early 1930s (PE21/31).
In The Etymologies of the 1930s the root ᴹ√LOP was glossed “horse”, and its derivatives ᴹQ. olombo and N. lobor had only that sense (EtyAC/LOP), but horse words were usually derived from ᴹ√ROK from the 1930s and later. The word Q. lopoldi “rabbits” appeared in some 1965 notes on Númenor, so it seems likely √LOP remained valid in some form. Another possibly related late word is S. ✱laba- “hop” as in S. Labadal “Hopafoot” (UT/60).
Neo-Eldarin: For purposes of Neo-Eldarin, I think it is worth retaining ᴹ√LOP with a verbal sense “✱run (of animals), gallop, lope”. In this way, it can remain the basis for rabbit words based on their loping run. The horse words from this root might be specialized for heavier loping horses like destriers, since ᴹQ. rokko was more specifically referred to a “swift horse” (EtyAC/ROK).
ed(er)
root. open
A deleted root in The Etymologies of the 1930s with the gloss “open” and the forms √ED and extended √EDÉR, but it had no derivatives (EtyAC/ED).
kelun
noun. river
sed
root. rest
yan
root. give
A root in The Etymologies of the 1930s glossed “give” with derivatives ON. yanta- “give” and ᴹQ. Ariante “Day-bringer” (EtyAC/YAN²). Tolkien marked this entry with a “?”, and elsewhere in The Etymologies he derived ᴹQ. anta-/N. anna- “give” from ᴹ√ANA (Ety/ANA¹), so I suspect this root was a transient idea.
pantā
adjective. open
andā
adjective. long
ezdē
noun. rest
geiā
adverb. ever
gālæ
noun. light
ithil
noun. moon
k’lā
noun. light
lūme
noun. time
parmā
noun. book
ranā
proper name. Moon
sir
root. flow
tainā
adjective. long
tal
root. foot
tāl
noun. foot
tārā
adjective. lofty
ñol-
noun. smell
A root in The Etymologies of the 1930s meaning “dust”, with derivatives ᴹQ. asto and N. ast of the same meaning (Ety/ÁS-AT).