tim

noun. spark, star

A noun for “star”, more literally meaning “spark” derived from primitive ᴹ✶tinmē (Ety/TIN). As suggested by Helge Fauskanger (AL-Ilkorin/tim), probably the primitive [[ilk|[nm] became [mm]]] in Ilkorin to produce the final form.

Conceptual Development: Edward Kloczko suggested that Tolkien later reused this word as North Sindarin tim with the same meaning (Tyalië Tyelelliéva #9).

dûm

noun. twilight

A noun for “twilight” developed from primitive ᴹ✶dōmi (Ety/DOMO), where the long [[ilk|[ō] became [ū] before [m]]].

ungol

noun. darkness

A noun for “darkness” developed from the root ᴹ√UÑG (Ety/UÑG), perhaps from a primitive form ✱✶uñglē̆ [uŋglē̆] as suggested by Helge Fauskanger (AL-Ilkorin/ungol): after the [[ilk|primitive final [e] was lost]], the resulting [[ilk|final [l] would become syllabic and develop into [-ol]]].