A root in The Etymologies of the 1930s glossed “dread” with two variations: ᴹ√GOS and ᴹ√GOTH (Ety/GOS). It was an element in quite a few names in Silmarillion drafts from the 1930s, such as ᴹQ. Mandos “Dread Imprisoner” (Ety/MBAD), ᴹQ. Osse (Ety/GOS), N. Gothmog (Ety/MBAW), N. Tauros “Forest-Dread” (Ety/TÁWAR), and N. Dor-Daideloth “Land of the Shadow of Dread” (LR/405), the last of these containing N. deloth “abhorrence, detestation, loathing” = ᴹ√DYEL + ᴹ√GOTH (Ety/DYEL).
In Tolkien’s later writings, many of these names were given new forms or etymologies: Q. Mandos “Castle of Custody” = mando + osto (MR/350); Q. Ossë as an adaptation of his Valarin name Oš(o)šai (WJ/400); S. Tauron “Forester” (PM/358). This calls into question whether ᴹ√GOS or ᴹ√GOTH survived as a root. It does have a few useful derivatives for the purposes of Neo-Eldarin, however, such as N. gosta- “fear exceedingly”.