chrono - Dwarrows

No reviewer (that I have seen), although all have carefully used the correct dwarfs themselves, has commented on the fact (which I only became conscious of through reviews) that I use throughout the 'incorrect' plural dwarves. I am afraid it is just a piece of private bad grammar, rather shocking in a philologist; but I shall have to go on with it. Perhaps my dwarf – since he and the Gnome are only translations into approximate equivalents of creatures with different names and rather different functions in their own world – may be allowed a peculiar plural. The real 'historical' plural of dwarf (like teeth of tooth) is dwarrows, anyway: rather a nice word, but a bit too archaic. Still I rather wish I had used the word dwarrow.

The Letters of J.R.R. Tolkien 17: To Stanley Unwin, Chairman of Allen & Unwin. October 1937