quantum

From Late Latin quantum, noun use of neuter form of Latin quantus (“how much”).

• (Received Pronunciation) IPA^(key): /ˈkwɒntəm/
• (General American) IPA^(key): /ˈkwɑntəm/
  • (US, Canada) IPA^(key): (enunciated) [ˈkʰwɑ̃ntʰə̃m], (common flapped realization) [ˈkʰwɑ̃ɾ̃ə̃m]

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    (enunciated)

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    (flapped)

Note: in General American, the enunciated form is more common when the word is used on its own; but in connected speech, when it is used as a modifier (as in quantum mechanics), the flapped form is more common.

quantum (countable and uncountable, plural quantums or quanta)

1. (now chiefly South Asia or law) The total amount of something; quantity. [from 17th c.] quotations ▼
   • 1749, Henry Fielding, Tom Jones, Folio Society, published 1973, page 416:

     The reader will perhaps be curious to know the quantum of this present, but we cannot satisfy his curiosity.

   • 1790, Edmund Burke, Reflections on the Revolution in France, Oxford, published 2009, page 142:

     A certain quantum of power must always exist in the community, in some hands, and under some appellation.

   • 1997, Kiran Nagarkar, Cuckold, HarperCollins, published 2013, page 375:

     Otherwise I will have given the lie to my maxim that whether you work eight or twenty hours, the quantum of work that gets done on a normal day is the same.

   • 2008 May 21, The Times of India:

     The Congress's core ministerial panel on Friday gave its green signal to raising motor fuel prices but the quantum of increase emerged as a hitch.

   1. (law) The amount of compensation awarded to a successful party in a lawsuit.
   2. (law) The length or magnitude of the sentence handed down to someone who has been found guilty of a crime.
2. The amount or quantity observably present, or available. [from 18th c.] quotations ▼
   • 1979, John Le Carré, Smiley's People, Folio Society, published 2010, page 96:

     Each man has only a quantum of compassion, he argued, and mine is used up for the day.

   • 1999, Sigmund Freud, translated by Joyce Crick, The Interpretation of Dreams, Oxford, published 2008, page 34:

     The dream of flying, according to Strümpell, is the appropriate image used by the psyche to interpret the quantum of stimulus [translating Reizquantum] proceeding from the rise and fall of the lungs when the cutaneous sensation of the thorax has simultaneously sunk into unconsciousness.

3. (physics) The smallest possible, and therefore indivisible, unit of a given quantity or quantifiable phenomenon. [from 20th c.] quotations ▼
   • 2002, David C Cassidy et al., Understanding Physics, Birkhauser, page 602:

     The quantum of light energy was later called a photon.

4. (computing) The amount of time allocated for a thread to perform its work in a multithreaded environment.
5. (computing, uncountable) Ellipsis of quantum computing.

   Developing for quantum has never been more accessible.

6. (medicine) The minimum dose of a pathogen required to cause an infection. synonym ▲

   Synonym: infectious dose

7. (mathematics) A definite portion of a manifoldness, limited by a mark or by a boundary. quotations ▼
   • 1882, William Kingdon Clifford, Mathematical Papers:

     Defined parts of a manifoldness are called Quanta

quantum (not comparable)

1. Of a change, sudden or discrete, without intermediate stages.
2. (informal) Of a change, significant.
3. (physics) Involving quanta, quantum mechanics or other aspects of quantum physics. quotations ▼
   • 2012 January, Michael Riordan, “Tackling Infinity”, in American Scientist‎^[1], volume 100, number 1, archived from the original on 19 June 2017, page 86:

     Some of the most beautiful and thus appealing physical theories, including quantum electrodynamics and quantum gravity, have been dogged for decades by infinities that erupt when theorists try to prod their calculations into new domains. Getting rid of these nagging infinities has probably occupied far more effort than was spent in originating the theories.

   1. (computing theory) Relating to a quantum computer.
   antonym ▲

   Antonym: classical

• → French: quantum
• → Portuguese: quantum

• quantum on Wikipedia.Wikipedia

• IPA^(key): /kwantum/ [kwãn̪.t̪ũm]
• Rhymes: -antum, -um

quantum inan

1. alternative form of kuantu (“quantum”)

• “quantum”, in Euskaltzaindiaren Hiztegia [Dictionary of the Basque Academy] (in Basque), Euskaltzaindia [Royal Academy of the Basque Language]

From Latin quantum.

• IPA^(key): /kɑ̃.tɔm/, /kwɑ̃.tɔm/

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quantum m (plural quanta)

1. (physics) quantum

• “quantum”, in Trésor de la langue française informatisé [Digitized Treasury of the French Language], 2012

Unadapted borrowing from German Quantum, from Latin quantum. Doublet of quanto, which was also re-borrowed with the same meaning as quantum. First attested before 1930.

quantum m (plural quanta)

1. quantum synonym ▲

   Synonym: quanto

• (Classical Latin) IPA^(key): [ˈkʷan.tũː]
• (modern Italianate Ecclesiastical) IPA^(key): [ˈkʷan.tum]

quantum

1. inflection of quantus:
   1. nominative/accusative/vocative neuter singular
   2. accusative masculine singular

quantum (with genitive)

1. (when coupled with tantum) as much of […] as

   da mihi tantum aquae quantum vini ― give me as much of water as wine

2. how high, how dear, as dear as

• quantum libet
• quantum meruit
• quantum satis
• quantum valebant

• → Dutch: kvante (learned)
• → English: quantum (learned)
  • → French: quantum
  • → Portuguese: quantum
• French: quant
• → German: Quantum (learned)
• Italian: quanto
• Spanish: cuanto
• Portuguese: quanto

• “quantum”, in Charlton T. Lewis and Charles Short (1879), A Latin Dictionary, Oxford: Clarendon Press
• “quantum”, in Charlton T. Lewis (1891), An Elementary Latin Dictionary, New York: Harper & Brothers
• "quantum", in Charles du Fresne du Cange, Glossarium Mediæ et Infimæ Latinitatis (augmented edition with additions by D. P. Carpenterius, Adelungius and others, edited by Léopold Favre, 1883–1887)
• “quantum”, in Gaffiot, Félix (1934), Dictionnaire illustré latin-français, Hachette.
• Carl Meißner; Henry William Auden (1894), Latin Phrase-Book‎^[2], London: Macmillan and Co. 4 phrases
• Dizionario Latino, Olivetti

• quântum (rare)

Unadapted borrowing from Latin quantum. Doublet of quanto.

quantum m (plural quanta or (uncommon) quantuns)

1. (physics) quantum (indivisible unit of a given quantity)

• quanto
• quântico

• “quantum”, in Dicionário Aulete Digital (in Portuguese), Rio de Janeiro: Lexikon Editora Digital, 2008–2026
• “quantum”, in Dicionário Priberam da Língua Portuguesa (in Portuguese), Lisbon: Priberam, 2008–2026

Unadapted borrowing from Latin quantum.

• IPA^(key): /ˈkwantum/ [ˈkwãn̪.t̪ũm]
• Rhymes: -antum
• Syllabification: quan‧tum

quantum m (plural quanta)

1. alternative form of cuanto (“quantum”)

According to Royal Spanish Academy (RAE) prescriptions, unadapted foreign words should be written in italics in a text printed in roman type, and vice versa, and in quotation marks in a manuscript text or when italics are not available. In practice, this RAE prescription is not always followed.

• Seco, Manuel; Andrés, Olimpia; Ramos, Gabino (2023), “quantum”, in Diccionario del español actual (in Spanish), third digital edition, Fundación BBVA