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dictionary

n. · v.
US //ˈdɪkʃəˌnɛɹi// UK //dˈɪkʃənəɹi// dic·tio·nary
  1. 1 book of word meanings (n.)
    A1 Beginner

    a book or website that lists words in alphabetical order and explains what they mean.

    a reference work containing an alphabetical list of words with their definitions, pronunciations, and often etymological data.

    Example

    If you do not know what a word means, you should look it up in the dictionary.

    Example

    The student consulted a bilingual dictionary to ensure the nuances of the technical term were preserved in his translation.
  2. 2 alphabetical reference work (n.)
    B2 Upper Intermediate

    a book that gives information about a specific subject, with topics listed from A to Z.

    a specialized reference work or encyclopedia arranged alphabetically by subject matter.

    Example

    She bought a dictionary of gardening to help identify the plants in her new yard.

    Example

    The library recently acquired a comprehensive dictionary of architecture, covering styles from the classical era to the present day.
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  1. 3 computing data structure (n.)
    C1 Advanced Technical Computing

    a way of storing information in a computer where each piece of data has a unique name or key.

    an associative array or collection of key-value pairs, where each unique key maps to a specific value.

    Example

    The programmer used a dictionary to store the user's settings and their values.

    Example

    In Python, a dictionary is an efficient way to retrieve data when the unique identifier is known but the index is not.
  2. 4 knowledgeable person (n.)
    B2 Upper Intermediate Humorous

    a person who seems to know the meaning of every word or many facts.

    a person regarded as a vast repository of information or vocabulary.

    Example

    My grandfather is a walking dictionary; he can tell you the history of almost any word.

    Example

    The professor was a living dictionary of medieval history, capable of citing obscure dates and names without ever glancing at his notes.
  3. 5 to look up or record (v.)
    C2 Proficiency Formal

    to look for a word in a dictionary or to add a new word to one.

    to search for a term in a reference work or to include a lexical item within a formal lexicon.

    Example

    The editors decided to dictionary the new slang term after it became popular nationwide.

    Example

    The linguist spent years attempting to dictionary the dying dialect before its last native speakers passed away.
Origin

Etymology tree Proto-Indo-European *deyḱ- Proto-Indo-European *déyḱeti Proto-Italic *deikō Medieval Latin dīcō Proto-Indo-European *-tisder. Proto-Italic *-tjō Medieval Latin -tiō Medieval Latin dictiō Proto-Indo-European *-yósder. Proto-Italic *-āsios Medieval Latin -ārius Medieval Latin -ārium Medieval Latin dictiōnāriumlbor. Middle English dixionare English dictionary From Middle English dixionare, a learned borrowing from Medieval Latin dictiōnārium, from Latin dictiōnārius, from dictiō (“a speaking”), from dictus, perfect past participle of dīcō (“to speak”) + -ārium (“room, place”). By surface analysis, diction + -ary.

Idioms1 entry

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