According to WJ/301, the expression tôl acharn "vengeance comes" was later changed to tûl acharn by Tolkien
Noldorin
orthor-
verb. to master, conquer
orthor
verb. (he) masters, conquers
orthor-
verb. to master, conquer
ortha-
verb. to raise
blâb
verb. (he) flaps, beats
heron
noun. master
hîr
noun. master, lord
lhammas
noun. account of tongues
lhâf
verb. (he) licks
lhôd
verb. (he) floats
osgar
verb. (he) cuts, amputates
síla
verb. (he) shines white
sôg
verb. (he) drinks
thia
verb. it appears
tôg
verb. (he) leads, brings
tôl
verb. (he) comes
The Etymologies seem to list this word as a noun, but it is clearly the third person singular of the verb