According to WJ/301, the expression tôl acharn "vengeance comes" was later changed to tûl acharn by Tolkien
Noldorin
he
pronoun. she
he
pronoun. she
hen
pronoun. she
hen(e)
pronoun. she
hene
pronoun. she
ho
pronoun. he
ho
pronoun. he
hon
pronoun. he
hon(o)
pronoun. he
hono
pronoun. he
blâb
verb. (he) flaps, beats
tôl
verb. (he) comes
lhâf
verb. (he) licks
lhôd
verb. (he) floats
orthor
verb. (he) masters, conquers
osgar
verb. (he) cuts, amputates
síla
verb. (he) shines white
sôg
verb. (he) drinks
tôg
verb. (he) leads, brings
The Etymologies seem to list this word as a noun, but it is clearly the third person singular of the verb