Compliled from a large number of Tibetan and Sanskrit texts, this dictionary is the culmination of 12 years of labor. The Tibetan words are alphabetized with their accepted Sanskrit equivalents and followed by the English meaning. All technical terms are illustrated with excerpts from Sanskrit-Buddhist and Tibetan works.
Sarat Chandra Das (18 July 1849 – 5 January 1917) was an Indian scholar of Tibetan language and culture most noted for his two journeys to Tibet in 1879 and in 1881–1882.
A huge, but handy, Tibetan dictionary, with many many definitions. It's very difficult, though, to learn how to use it, because you need to know what letters are silent to find a word. The transliteration next to each Tibetan word is a bit different from Wylie, but they indicated the silent letters with an underline. It's also nice that some geographical names as well as Buddhist terms (along with their Sanskrit equivalent) are found as well.