中土世界的歷史
The Lhammas (pronounced ) is a work of fictional sociolinguistics by J. R. R. Tolkien. It was published in "The Lost Road and Other Writings" (1987), volume five of "The History of Middle-earth" series. The word "lhammas" is a Sindarin word meaning "account of tongues". In Tolkien's later development of Sindarin he changed the rules governing initial "l-" and "r-" whereby they no-longer became devoiced, resulting in the word becoming "lammas" ()