Dictionaries will help you to understand the meaning and the pronunciation of words.
The Oxford English Dictionary - ONLINE: An excellent electronic dictionary giving the meaning, history, and pronunciation of words -- past and present -- from across the English-speaking world.
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Fowler's Dictionary of Modern English Usage - IN PRINT: In the Killam Library Reference Collection at CALL NUMBER: PE 1464 F65 2015
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Shorter Slang Dictionary (2003) - ONLINE: This new collection brings together some 5,000 contemporary slang expressions originating in all parts of the English-speaking world. It gives clear and concise definitions of each word, supplemented by examples of their use and information about where and when they came into being.
Encyclopedias can be print or electronic and contain general information on many different areas of knowledge.
Credo Reference- ONLINE: An electronic encyclopedia containing lots of information about many, many different topics. A great source to learn the basics about a topic.
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Gale Virtual Reference Library - ONLINE: Provides the fulltext of many different reference books, including encyclopedias, handbooks, and dictionaries in a wide range of subject areas.