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dictionary

American  
[dik-shuh-ner-ee] / ˈdɪk ʃəˌnɛr i /

noun

  • dictionaries
    plural
  1. a book or digital resource (such as Dictionary.com) containing a selection of words and information about their meanings, pronunciations, etymologies, inflected forms, derived forms, etc., in either the same or another language; lexicon; glossary.

    an unabridged dictionary of English;

    a Japanese–English dictionary.

  2. a book or digital resource giving information on a particular subject or on a particular class of words, names, or facts, usually arranged alphabetically.

    a biographical dictionary;

    a dictionary of mathematics.

  3. Computers.

    1. a list of codes, terms, keys, etc., and their meanings, used by a computer program or system.

    2. a selection of words used by a piece of software, such as a word-processing program, to check the spelling of text entered.


dictionary British  
/ ˈdɪkʃənərɪ, -ʃənrɪ /

noun

    1. a reference resource, in printed or electronic form, that consists of an alphabetical list of words with their meanings and parts of speech, and often a guide to accepted pronunciation and syllabification, irregular inflections of words, derived words of different parts of speech, and etymologies

    2. a similar reference work giving equivalent words in two or more languages. Such dictionaries often consist of two or more parts, in each of which the alphabetical list is given in a different language

      a German-English dictionary

    3. ( as modifier ) See also glossary lexicon thesaurus

      a dictionary definition

  1. a reference publication listing words or terms of a particular subject or activity, giving information about their meanings and other attributes

    a dictionary of gardening

  2. a collection of information or examples with the entries alphabetically arranged

    a dictionary of quotations

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Noun Inflected Forms

Etymology

Origin of dictionary

First recorded in 1570–80; from Medieval Latin dictiōnārium, dictiōnārius, from Late Latin dictiōn- stem of dictiō “word” + -ārium, -ārius adjective and noun suffix; see diction ( def. ), -ary ( def. )

Explanation

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."

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Vocabulary lists containing dictionary

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

A walking dictionary of Chinatown, Yu has been vocal about how “the older, poorer residents just can’t sustain a market.”

From Los Angeles Times Aug. 4, 2026

On that view, the statute’s design reveals Congress’ objective every bit as clearly as any dictionary definition.

From Slate Jun. 26, 2026

To consider the word, I looked up its definition in Salon’s dictionary of choice.

From Salon Jun. 3, 2026

The brilliantly passive-aggressive faux talk show “Between Two Ferns With Zach Galifianakis” was web-based, but that’s defined as TV in my dictionary.

From Los Angeles Times Apr. 22, 2026

When I tried to look it up, I couldn’t because awe is in the dictionary and so is pear, but awe pear is not au pair.

From "Silent To The Bone" by E.L. Konigsburg

In his opinion for the court, Gorsuch relied heavily on dictionaries and cases published around the time the FAA was enacted.

From Slate Jun. 3, 2026

Middle age enrichment included income level at age 40, access to resources such as magazine subscriptions, dictionaries, and library cards, and how often participants visited places like museums or libraries.

From Science Daily Apr. 15, 2026

Such stature is perhaps what is lost with online dictionaries and what the new Collegiate hopes to regain.

From The Wall Street Journal Dec. 19, 2025

From 6-7 to skibidi and delulu, 2025 was the year when Generation Alpha slang entered everyday language and dictionaries with a vengeance.

From Barron's Nov. 26, 2025

And then there was a list of the dictionaries that Mrs. Granger thought would be “acceptable for home study. ”

From "Frindle" by Andrew Clements

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