A couple of months ago I discovered the a Black Speech word that I had missed – gûldur. I then didn’t know what to with the word and I have not analysed it. But as I read The History of Middle Earth Vol. 10 Morgoth’s Ring I found this clue. In the part
Athrabeth Finrod ah Andreth; Authors notes on the Commentary; Glossary: Ñoldor (p 350 in my paperback edition (2015). In this glossary Tolkien has written that:
The Quenya word ñólë meant ‘lore, knowledge’, but its Sindarin equivalent gûl, owing to its frequent use in such combinations as morgul (cf.Minas Morgul in The Lord of the Rings) was only used for evil or perverted knowledge, necromancy, sorcery. This word gûl was also used in the language of Mordor.
From the compound ‘nazgûl’ analysed as nazg “ring” + ‘gûl’ “wraith” or “any one of the major invisible servants of Sauron dominated entirely by his will (A Tolkien Compass)”. The word ‘gûl’ is very similar to the Elvish word root NGOL “wise” or “wisdom” and Primitive Elvish ñgôlê “Science/Philosophy” and identical to Sindarin gûl “deep knowledge; perverted or evil knowledge, sorcery, necromancy, black arts, magic”.
The interpretation for Zhâburi is that ‘gûl’ means someone who has gained deep knowledge through the black arts of Sauron which also means that one is dominated by his will and one’s perspective of the world is completely that of the Dark lord.
The word gûl in the Black Speech is probably a loan word from Sindarin but the root word NGOL and Primitive Elvish ñgôlê would give us gûl in my Anband Orcish and so in Zhâburi as well.
So then about the word gûldur. The most simple analysis would be that it is a compound word of gûl and dur the latter being related to durb– (to rule) Quenya tur– tur- v. “to master, conquer, dominate, win”. So gûldur would then mean something like “(black) lore dominating” or “to master by the means of (evil) lore”.
So what about the ‘b’ in ‘durb’? I have been thinking of this b (and the one in ‘gimb-‘ (to find) for a long time. My solution has been to view it as a derivative suffix. If we treat gûldur as a compound of ‘gûl’ and ‘dur’ then this is a elegant solution so now I can settle that question (and maybe publish my list of derivative suffixes soon).
So what about Morgoth’s Ring? I actually started to read books from The History of Middle Earth to find out more of the theological and philosophical aspects of Tolkien’s Arda so that I could create/enlarge Sauron’s theology. And in Morgoth’s Ring I have found i not plenty so at least very relevant material in the text Athrabeth Finrod ah Andreth.