A word for “horse” in The Etymologies of the 1930s, derived from the root ᴹ√LOP (EtyAC/LOP). It did not appear in The Etymologies as published in The Lost Road, but Carl Hostetter and Patrick Wynne reported it in their Addenda and Corrigenda to the Etymologies (VT45/28).

Conceptual Development: The similar word G. lobros “steed, horse” appeared in the Gnomish Lexicon of the 1910s (GL/54), clearly based on the early root ᴱ√LOPO that was the basis for “horse” words in the Qenya Lexicon (QL/56). In The Etymologies, Tolkien first gave the root as ᴹ√LOB and the Noldorin form as {lum >>} lhuv, perhaps from *lōbo, but these were deleted and replaced by ᴹ√LOP and lobor.

Neo-Sindarin: Since Tolkien sometimes described S. roch as a “swift horse”, I’d assume lobor was a heavy riding horse or war horse.