Etymology: Isengard and Helms Deep

[William Cloud Hicklin]

The nature and content of VT took a dramatic turn after Carl H took over and made it a journal for shorter original JRRT linguistic material (PE handling the long-form works)

[William Cloud Hicklin]

There is also this, from 'Lowdham's Report on the Adunaic Language' associated with The Notion Club Papers (HME IX):

I think [Adunaic] came under some different influence [than 'Avallonian' or Elvish]. This influence I call Khazadian; because I have received a good many echoes of a curious tongue, also connected with what we should call the West of the Old World, that is associated with the name Khazad. Now this resembles Adunaic phonetically, and it seems also in some points of vocabulary and structure; but it is precisely at the points where Adunaic most differs from Avallonian that it approaches nearest to Khazadian.

[...]

The majority of the word-bases of Adunaic were triconsonantal. This structure is somewhat reminiscent of Semitic; and in this point Adunaic shows affinity with Khazadian rather than with Nimrian [Elvish again, here the Adunaic name for it]. For though Nimrian has many triconsonantal stems (other than products of normal suffixion), such as the stem menel cited above, these are rarer in Nimrian, and are mostly the stems of nouns....

[William Cloud Hicklin]

And this, from the 1966 BBC interview:

The dwarves, of course, are quite obviously, couldn’t you say that in many ways they remind you of the Jews? Their words are Semitic obviously, constructed to be Semitic.