The Etymologies is a document edited by
Christopher Tolkien which appears in the
History of Middle-earth:
The Lost Road and Other Writings. Christopher Tolkien described it as "a remarkable document." It is essentially a list of "roots" which
J. R. R. Tolkien used as building blocks in creating the Elvish languages of Arda, namely Quenya and Sindarin. Christopher Tolkien said in his introduction that his father was "more interested in the processes of change than he was in displaying the structure and use of the languages at any given time." (Lost Road p. 378.)
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