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Cambridge Dictionaries Online: This site allows searching from four dictionaries of the English language from Cambridge University Press.

AlphaDictionary - Search 992 dictionaries at once.

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Social Sciences (Library Science) English<>Spanish Dictionary - Compilation of terminology in the social sciences that students and professionals generally encounter when reading professional literature with a particular emphasis on information organisation and retrieval. 107.000+ entries. Google PageRank 7/10. Internet-accessible since 2000. Babylon version also available.