LOL! Maybe he was working on the ol' 10% rumour
- Thorin, Balin, Nori, Gandalf, Bombur ... but there are also Thrain Thror, Nain & Dain. Also Welsh based names - 'Gorhendad' from the Brandybuck line, and most Hobbit names are Anglo Saxon based: Angles, Saxons, and Jutes - also Medieval, Middle & Old English, Ancient Irish, Ancient Cornish, Latin, Old High German, Old Norse/Icelandic. The English names Took & Tuck come from old Norse
'taka' meaning to 'take' - then into Old English
'tucian' meaning to disturb - then Took.
For example: Dwarf is derived from Dweorh (Old English) - Dwergr (Old Norse) - Twerg (Old High German) - Dvairgaz (Prehistoric German) - Dhwergwhos (Indo-European) thus translating 'something small'.
The Dwarfs names come from the 'Edda' the 'Dvergatal' (The lost tale of the Dwarfs) - in Vikings mythology - the Dwarfs roll. Tolkien used this role ...
The Drarf names themselves tell of the quest of the Dwarfs ... Tolkien also used the name 'Eikinskjaldi' meaning 'he of the Oakenshield' which he gave to Thorin. 'Thrain' translated, means stuborn. Dain means deadly, Bombur translated means 'bulging', Nori means 'Peewee', Balin means 'burning one', Ori means 'furious', Gloin means 'glowing one' (riches and glory).
Gandalf started life out as Old Nordic/Icelandic - 'Gandalfr' ... 'Gand' meaning magical powers of astral travel, 'Gandr' a socerers magic stick, and 'Alf' means elfen or white. The name 'Gandalfr' is also mentioned in the 'Dvergatal'.
Bilbo started life as Bingo
, but the name Bilbo was a short pointy dagger in Shakepeares time - from the name of a 15th century Portuguese city - Balboa, where it was made.
Tolkien made his names from old languages - as the words had meanings - and many meaningful words are strung together to form the name - its not unlike names of 'old' or recognized names especially in old lore and fairy stories. He also credited and mentioned his influences - such as George McDonalds 1872
The Princess & the Goblin - Beowulf, is a large influence on his works.
But as for Gandalf the Grey, Gandalf the White, Mithrandir, The Grey pilgrim ..etc ... from LOTR - he's got a trademark to the licensee 'New Line' ... and copyright in character from the books by Tolkien ...