A dictionary is a collection of words and their definitions (and sometimes other information). Such collections are usually printed as books, but some are now designed for use on computers.

Dictionary originally came from the Latin word dictionarius, meaning "a manual or book of words." A dictionary is most commonly used to look up the definitions of particular words, but other information, such as etymology and usage guidelines, often appears as well. Electronic dictionaries can include even more information, like slang and popular texting acronyms, such as "ttyn," which stands for "talk to you never."

Definitions of dictionary
  1. noun
    a reference book containing an alphabetical list of words with information about them
    synonyms: lexicon
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    Oxford English Dictionary
    an unabridged dictionary constructed on historical principles
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    bilingual dictionary
    a dictionary giving equivalent words in two languages
    collegiate dictionary, desk dictionary
    an abridged dictionary of a size convenient to hold in the hand
    etymological dictionary
    a dictionary giving the historical origins of each word
    a geographical dictionary (as at the back of an atlas)
    learner's dictionary, school dictionary
    a dictionary specially written for those learning a foreign language
    little dictionary, pocket dictionary
    a dictionary that is small enough to carry in your pocket
    spell-checker, spelling checker
    an electronic dictionary in a word processor that can be used to catch misspelled words
    unabridged, unabridged dictionary
    a dictionary that has not been shortened by the omitting terms or definitions; a comprehensive dictionary
    type of:
    a reference book containing words (usually with their meanings)
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