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noun dic·tio·nary \ˈdik-shə-ˌner-ē, -ˌne-rē\

Simple Definition of dictionary

  • : a reference book that contains words listed in alphabetical order and that gives information about the words' meanings, forms, pronunciations, etc.

  • : a reference book that lists in alphabetical order the words of one language and shows their meanings or translations in a different language

  • : a reference book that lists in alphabetical order words that relate to a particular subject along with their definitions and uses

Source: Merriam-Webster's Learner's Dictionary

Full Definition of dictionary



  1. 1 :  a reference source in print or electronic form containing words usually alphabetically arranged along with information about their forms, pronunciations, functions, etymologies, meanings, and syntactical and idiomatic uses

  2. 2 :  a reference book listing alphabetically terms or names important to a particular subject or activity along with discussion of their meanings and applications

  3. 3 :  a reference book listing alphabetically the words of one language and showing their meanings or translations in another language

  4. 4 :  a computerized list (as of items of data or words) used for reference (as for information retrieval or word processing)

Examples of dictionary in a sentence

  1. Famed for his dictionary, “Rambler” essays and The Lives of the English Poets, Samuel Johnson (1709-1784) remains one of the most-quoted and carefully observed authors who ever lived. —Publishers Weekly, 21 July 2008

  2. I still read relatively slowly in Yiddish, with frequent recourse to a dictionary, and my first year of graduate school found me at my desk till two or three in the morning every night … —Aaron Lansky, Outwitting History, 2004

  3. Look it up in the dictionary.

  4. <try to develop the habit of going to the dictionary whenever you encounter an unfamiliar word>

Origin and Etymology of dictionary

Medieval Latin dictionarium, from Late Latin diction-, dictio word, from Latin, speaking

First Known Use: 1526

Rhymes with dictionary

actuary, adversary, airy-fairy, ancillary, antiquary, apiary, arbitrary, aviary, axillary, bacillary, beriberi, bestiary, biliary, black raspberry, Bloody Mary, boysenberry, breviary, budgetary, calamari, calamary, candleberry, Canterbury, capillary, carpellary, cassowary, catenary, cautionary, cavitary, cemetery, centenary, certiorari, checkerberry, chinaberry, cometary, commentary, commissary, condottiere, coralberry, corollary, coronary, culinary, customary, dietary, dignitary, dromedary, dysentery, elderberry, emissary, estuary, farkleberry, February, formulary, fragmentary, fritillary, functionary, funerary, honorary, huckleberry, intermarry, janissary, January, lamasery, lapidary, lectionary, legendary, legionary, lingonberry, literary, loganberry, luminary, mammillary, mandatary, maxillary, medullary, mercenary, miliary, military, millenary, milliary, millinery, missionary, momentary, monastery, mortuary, necessary, ordinary, ossuary, partridgeberry, pensionary, pigmentary, planetary, Pondicherry, prebendary, presbytery, pulmonary, quaternary, red mulberry, reliquary, rowanberry, salivary, salmonberry, salutary, sanctuary, sanguinary, sanitary, secondary, secretary, sedentary, seminary, silverberry, solitary, sour cherry, stationary, stationery, statuary, subcontrary, sublunary, sugarberry, sumptuary, syllabary, temporary, tertiary, thimbleberry, Tipperary, Tom and Jerry, topiary, tributary, tutelary, Typhoid Mary, unitary, urinary, vestiary, Virgin Mary, visionary, voluntary, vulnerary, Waterbury, whortleberry, winterberry

DICTIONARY Defined for Kids


noun dic·tio·nary \ˈdik-shə-ˌner-ē\

Definition of dictionary for Students



  1. 1 :  a book giving the meaning and usually the pronunciation of words listed in alphabetical order

  2. 2 :  a reference book explaining words of a particular subject listed in alphabetical order <a medical dictionary>

  3. 3 :  a book listing words of one language in alphabetical order with definitions in another language

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