An Ilkorin adjective meaning “nimble, active, running free” developed from the root ᴹ√LEK, an element in the river name Legolin (Ety/LEK). It probably developed from a primitive form *✶leklā: after the primitive final [a] was lost, the resulting final [l] became syllabic and developed into [-ol], as suggested by Helge Fauskanger (AL-Ilkorin/legol).

Conceptual Development: Tolkien did not revise the river name Legolin after abandoning the Ilkorin language, so it is possible he reconceived this word as Sindarin. Its phonetic development from *✶leklā would have produced the same result in Noldorin/Sindarin.