A rejected draft version of the Adûnaic name for Morgoth translated “Lord”, replaced by Arûn of the same meaning (SD/376). It is transparently a derivative of the Elvish root ᴹ√KHER, as suggested by Carl Hostetter and Patrick Wynn (AAD/18). A later form of this word, ✱khôr “lord”, may appears as an element in the name Adûnakhôr “Lord of the West”.
Primitive elvish
kher
root. possess, possess, [ᴹ√] rule, govern, [ᴱ√] have power
khēr
noun. lord, master
kherū
noun. lord, master
árātō
noun. lord
The basic root for rulership was √KHER for most of Tolkien’s life. The root appeared as ᴱ√HERE “rule, have power” in the Qenya Lexicon of the 1910s, and in this period already had the derivative ᴱQ. heru “lord” and ᴱQ. heri “lady” (QL/40), words that retained the same form and meaning throughout Tolkien’s life. Gnomish derivatives from this period include G. herma “protection, lordship, sway”, G. hermon “lord”, G. hîr “care, anxiety; heed”, and G. hiril “queen†, princess” (GL/49).
In The Etymologies of the 1930s these last two Gnomish words became N. hîr “master” and N. hiril “lady” as derivatives of ᴹ√KHER “rule, govern, possess”; the words ᴹQ. heru/ᴹQ. heri reappeared as well (Ety/KHER). All four of these words reappeared frequently in Tolkien’s later writing, though S. hîr was more typically glossed “lord” (PM/210; SD/129; VT41/9; Let/382; UT/318). The root √KHER itself reappeared in a 1954 letter to Naomi Mitchison with the gloss “possess” (Let/178).