[The Squatter of Amon Rûdh]

Maybe the problem is that you're using the "Concise" rather than the "Unabridged" Oxford Dictionary

I was considering the same possibility. Have you seen how much the full Oxford costs, though? I shall have to buy a copy from 1952 just to be able to afford it (mind you, not many good words have been coined since then, so it's probably just as good).
I now feel thoroughly humbled in the etymological stakes, so I shall pop off and fail to fill in the Times crossword.