from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A reference work containing an alphabetical list of words, with information given for each word, usually including meaning, pronunciation, and etymology.
  • noun A reference work containing an alphabetical list of words in one language with their translations in another language.
  • noun A reference work containing an alphabetical list of words in a particular category or subject with specialized information about them.
  • noun A list of words stored in machine-readable form for reference, as by spelling-checking software.

from The Century Dictionary.

  • noun A book containing either all or the principal words of a language, or words of one or more specified classes, arranged in a stated order, usually alphabetical, with definitions or explanations of their meanings and other information concerning them, expressed either in the same or in another language; a word-book; a lexicon; a vocabulary: as, an English dictionary; a Greek and Latin dictionary; a French-English or an English-French dictionary.
  • noun Synonyms Glossary, Lexicon, etc. See vocabulary.
  • Pertaining to or contained in a dictionary.

from the GNU version of the Collaborative International Dictionary of English.

  • noun A book containing the words of a language, arranged alphabetically, with explanations of their meanings; a lexicon; a vocabulary; a wordbook.
  • noun Hence, a book containing the words belonging to any system or province of knowledge, arranged alphabetically

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A reference work with a list of words from one or more languages, normally ordered alphabetically and explaining each word's meaning and sometimes containing information on its etymology, usage, translations, and other data.
  • noun computing An associative array, a data structure where each value is referenced by a particular key, analogous to words and definitions in a physical dictionary.
  • verb transitive To look up in a dictionary
  • verb transitive To add to a dictionary
  • verb intransitive To appear in a dictionary

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun a reference book containing an alphabetical list of words with information about them


from The American Heritage® Dictionary of the English Language, 4th Edition

[Medieval Latin dictiōnārium, from Latin dictiō, dictiōn-, diction; see diction.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

Medieval Latin dictionarium, from Latin dictionarius, from dictio ("speaking"), from dictus, perfect past participle of dīcō ("speak") + -arium ("room, place").


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  • Fun Fact about English:

    There are somewhere between 450,000 and 600,000 unique words in the various English dictionaries (OED, MW).

    December 20, 2006

  • Another fun fact:

    Modern English is rooted almost equally in Latin, French and Germanic. The percentages, provided by Oxford Dictionaries, are below:

    Latin, including modern scientific and technical Latin: 28.24%

    French, including Old French and early Anglo-French: 28.3%

    Old and Middle English, Old Norse, and Dutch: 25%

    Greek: 5.32%

    No etymology given: 4.03%

    Derived from proper names: 3.28%

    All other languages contributed less than 1%

    December 20, 2006

  • Derren Brown memorized the dictionary.

    January 22, 2008

  • Ho. Lee. Cow.

    January 22, 2008

  • I like looking up "dictionary" in dictionaries and seeing how the definitions of themselves vary

    February 26, 2008

  • The Onion Historical Archives has an article about this.

    October 7, 2008

  • now has *free* auditory pronunciation. I'm not too dismayed to learn that I've been mispronouncing the s-word.

    October 11, 2008

  • Like Wordie, but with photos. :-)

    February 26, 2009

  • Oh, wow!

    February 26, 2009

  • I never understood why a dictionary is considered good for learning the correct way to spell a word. If I don't know how the word is spelled, how can I look it up in the dictionary?

    February 27, 2009

  • TBT, you would probably have some idea about how the word is spelled, wouldn't you? Often the problematic part of the word comes in the middle or the end (e.g. -able or -ible, -ant or -ent), so you know enough to look the word up and discover the correct spelling. If the word starts in a quirky way, like the name of our friend pterodactyl, then you might indeed be stumped, but after a while you may even start recognizing some of these deceptive spellings, and know that if the word isn't spelled one way then it is probably spelled another way. Most people, I suspect, use dictionaries to confirm or correct spellings they think they know.

    February 27, 2009

  • Website idea:

    February 27, 2009

  • Mnthkeis Tatbbby was bnieg ftoiuaces (ro otssnettulaioy spiutd). Tugohh I msut csnoefs to hinvag gaert dfulticfeis tirnyg to fnid the Dierow Wrdoie Roidew Drowie Weirdo Oridew Edwiro Owired Iwdero stie ervey mite I loogn.

    February 27, 2009

  • siulahior!

    February 27, 2009

  • Very funny, Fox. Maybe s/he was being facetious, but I suspect the latter.

    February 27, 2009

  • Some online dictionaries offer wildcard searches. So if you think mellifluous is spelled a certain way you can type in mal* and see what happens. The results show maliciousness then malign so it's clear it doesn't start with mal-. Then you'd try mel* (as it's the only other vowel that sounds about right) and you'd be on your way.

    February 27, 2009

  • I've always admired bilby's mollifluous maunderings.

    February 27, 2009

  • Oooh! Bonus points for using the word maunderings. I like finding examples of words that you won't find in thesauruses even though their synonyms are listed.

    February 27, 2009

  • My favorite online dictionary, OneLook, offers not only wildcards but also a "search by meaning" tool (the colon). For example, if you wanted to find words that start with M and mean "smooth", you could go to OneLook and type in "m*:smooth". It's useful not only for finding spellings but also for finding words you don't know.

    I first discovered OneLook by way of Wordie, so let me just pause and say a hearty "Thanks, John!".

    February 27, 2009

  • Ditto, ptero. I now use OneLook more than any of the other online dictionaries.

    February 27, 2009

  • Thanks pterodactyl, I wasn't aware of the tool you mentioned. I'm keen to check it out ... there goes the weekend!

    February 27, 2009

  • And I was just going to do a quick wordie check and start cleaning my house.... Hmmmmm. Where to begin? I think I'll start with l*:slacker.

    BTW: Look at the word of the day today on OneLook!

    February 28, 2009

  • A fine usage right here.

    September 2, 2009

  • This word was chosen as Wordnik word of the day.

    November 11, 2009

  • Lexicography is a science of making dictionaries.

    November 15, 2009