The following is a list of words/names and their meanings and/or etymologies that I have documented. Some of these were originally elsewhere e.g. the document on the History of The Lord of the Rings but i have tried to consolidate them into this document (though this does not mean there won't be some redundancy).

The prefix 'Mor'

The Elvish prefix Mor means Black but there are many places it is used. Here are some of them.

Moria

In The Lord of the Rings this meant Black Pit; another time it meant Black Gulf.

Morgul (at one point Morgol)

This name can be seen in e.g. Minas Morgul which was what was once Minas Ithil but after being captured by the Nazgûl it was the Tower of (Black) Sorcery (though it had other names).

Morgai

Sam encounters this just as he enters Mordor. On pg. 899 of the 50th anniversary edition of The Lord of the Rings (HarperCollins Publisher) it's described like this:

Hard and cruel and bitter was the land that met his gaze. Before his feet the highest ridge of the Ephel Dúath fell steeply in great cliffs down into a dark trough, on the further side of which there rose another ridge, much lower, its edge notched and jagged with crags like fangs that stood out black against the red light behind them: it was the grim Morgai, the inner ring of the fences of the land. Far beyond it, but almost straight ahead, across a wide lake of darkness dotted with tiny fires, there was a great burning glow; and from it rose in huge columns a swirling smoke, dusty red at the roots, black above where it merged into the billowing canopy that roofed in all the accursed land.

Sam was looking at Orodruin, the Mountain of Fire. [...]

Morgoth

Earlier known as Melkor ('He Who Arises in Might'), at that point mightiest of the Valar, Fëanor named him Morgoth after he colluded with Ungoliant(e) to darken the world and then steal the Silmarils (and other jewels but it was the Silmarils that were most coveted): Black Enemy, Black Foe; and no longer was he considered part of the Valar.

Morannon

This was the Black Gate of Mordor (Black Land, see next section): this was where Frodo with Gollum and his servant Sam first went but because it was closed Gollum would lead them to the other way; they would be captured by Faramir Captain of Gondor and they would be released and then Gollum would lead them on towards Mordor.

The suffix 'Dor'

Dor means Land, Country. Here are a couple examples.

Mordor

As above prefix Mor suggests this means Black Land. This would be where the Mountain of Fire was, which is where the One Ring was forged in secrecy (to rule over the other Rings of Power that had been made by the Elves with Sauron's guidance).

Gondor

This was Stone Land. Earlier it was just called Gond but that wasn't the final name. This was a kingdom in the South that is also where Aragorn was crowned King of the reunited kingdoms and where he wed the Lady Arwen of Rivendell.

Ents

This word which means Tree-folk derives from the Old English word eoten which means giant. The history of this is more complicated and I have a section in my commentary on the history of The Lord of the Rings document.

Fangorn/Treebeard

Fangorn is elvish literally for beard-(of)-tree.

Quickbeam

This is one of the many amazingly brilliant names by Tolkien and it's my favourite too! It goes beyond what most people probably even realise. This is how he is introduced and his explanation in The Lord of the Rings:

'Ha, hmm, my friends, let us go for a walk!' he said. 'I am Bregalad, that is Quickbeam in your language. But it is only a nickname, of course. They have called me that ever since I said yes to an elder Ent before he had finished his question.

But that's NOT the best part! To understand this you have to take a look at the dictionary:

quickbeam noun
another term for mountain ash (sense 1).

mountain ash noun
1 a small deciduous tree of the rose family, with compound leaves, white flowers, and red berries. Compare with rowan, Genus Sorbus, family Rosaceae: several species, in particular the North American S. americana.

The keyword is 'rowan': there were rowan-trees in Quickbeam's home! Is this actually surprising that Tolkien knew this? No I don't think so. Not only was he a philologist and lexicographer but he also loved trees!

Hobbits

I have already documented an amusing jest on the invention of the word hobbit in my History of Middle-earth document. I have also included some information on the names Samwise and Hamfast in the history of The Lord of the Rings document. But I will now elaborate more on these two names.

Samwise (Gamgee)

This as I said means 'halfwise, simple' but it derives from OE adjective samwís: stupid dull foolish.

Hamfast (Gamgee) - Sam's father

This meanwhile means 'stay-at-home' and it derives from OE hámfæst: resident settled in or owning a house.

Shelob

As I have noted in another place Lob is an old word for spider so it literally means She spider.