rok

root. run on foot, *horse, run on foot

This root was the basis for Elvish “horse” words starting in the 1930s. It first appeared as unglossed ᴹ√ROK in The Etymologies of the 1930s with the derivatives ᴹQ. rokko/N. roch “horse” (Ety/ROK). The root was given the gloss “run on foot” in a page of roots from the Quenya Verbal System (QVS) written in 1948, but that page was rejected. Primitive ✶rokkō “horse” was mentioned regularly in Tolkien’s later writing (Let/282; PE21/82; WJ/407), though in one place he clarified that it was more specifically a “swift horse for riding” (Let/382).