Many also provide example of proper word usage. Abridged dictionaries do not attempt to be as exhaustive or all-inclusive as unabridged dictionaries, but instead generally include only more commonly used words. Etymological dictionaries focus specifically on tracing the origins and evolution in words and word meanings. Subject dictionaries list and define words used in a specific discipline, profession, or area of specialized knowledge. Foreign language dictionaries list and define words in languages other than English.
Bilingual dictionaries match words in one language with their equivalents in another.
Usually, one of the languages is English. Polyglot dictionaries list equivalent words in three or more languages. Directory A list of persons, or of businesses or other types of organizations . Directories of other types of organizations also list officers, and well as function or purpose of the organization. Encyclopedia A book or set of books containing informational articles on a variety of subjects, usually arranged in alphabetical order.