A word meaning “mount, mountain” given as a derivative of √ORO/RŌ in Notes on Galadriel’s Song (NGS) from the late 1950s or early 1960s (PE17/64). In The Etymologies of the 1930s, ᴹQ. orto “mountain-top” appeared as a derivative of the root ᴹ√OROT (Ety/ÓROT).
Neo-Quenya: For purposes of Neo-Quenya, I think it is best to use orto with its 1930s sense “mountain-top”, and use Q. oron for “mountain”; see that entry for more details on the conceptual developments of this and related words.
orto noun "mountain-top" (ÓROT), "mount, mountain" (PE17:64)