con·​jec·​ture | \ kən-ˈjek-chər How to pronounce conjecture (audio) \

Definition of conjecture

 (Entry 1 of 2)

1a : inference formed without proof or sufficient evidence
b : a conclusion deduced by surmise or guesswork The criminal's motive remains a matter of conjecture.
c : a proposition (as in mathematics) before it has been proved or disproved
2 obsolete
a : interpretation of omens


conjectured; conjecturing\ kən-​ˈjek-​chə-​riŋ How to pronounce conjecture (audio) , -​ˈjek-​shriŋ \

Definition of conjecture (Entry 2 of 2)

transitive verb

1 : to arrive at or deduce by surmise or guesswork : guess scientists conjecturing that a disease is caused by a defective gene
2 : to make conjectures as to conjecture the meaning of a statement

Other Words from conjecture


conjecturer \ kən-​ˈjek-​chər-​ər How to pronounce conjecture (audio) \ noun

Synonyms for conjecture

Synonyms: Noun

Synonyms: Verb

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When the noun conjecture entered English in the 14th century, it referred to the act of interpreting signs or omens especially to make prognostications. That sense is now obsolete, but by the 16th century both the noun and verb conjecture had acquired the meanings of speculation and inference that we use today. Conjecture derives via Middle English and Middle French from the Latin verb conicere ("to throw together"), a combination of com- ("together") and jacere ("to throw").

Examples of conjecture in a Sentence

Noun Whether Columbus brought syphilis to the New World—or to the Old World—has been the subject of conjecture for at least 500 years. — Carl Zimmer, Science, 11 May 2001 … their voices rose in a chorus of conjecture and alarm, repeating the selfsame remark: "What is she going to do? I mean, is Betty going to faint?" — Edna O'Brien, New Yorker, 1 Jan. 1990 The reason why the French with superior man-power and American resources were doing so poorly was not beyond all conjecture. — Barbara W. Tuchman, The March of Folly, 1984 Peculiar features of early maps, which may have been nothing but a draftsman's whimsy, have inspired pages of vain conjecture. — Samuel Eliot Morison, The European Discovery of America, 1971 The biography includes conjectures about the writer's earliest ambitions. a conjecture about the extent of the injury Most of the book is conjecture, not fact. Verb It is fashionable now to conjecture that the Big Bang was caused by a random quantum fluctuation in a vacuum devoid of space and time. — Martin Gardner, Skeptical Inquirer, November/December 1998 … their traces left for future archaeologists to rediscover and perhaps to wonder or conjecture over. — Jane Jacobs, Cities and the Wealth of Nations, 1984 I am anxious to conjecture beforehand what may be expected from the sowing turneps [sic] in jaded ground, how much from the acre, & how large they will be? — Thomas Jefferson, letter, 29 Dec. 1794 Some have conjectured that the distant planet could sustain life. We only conjecture about his motives. See More
Recent Examples on the Web: Noun Though the new paper resolves van der Waerden’s conjecture, there are countless ways forward. Quanta Magazine, 21 Apr. 2022 Below, members of Forbes Communications Council share their best tips to help businesses enact the appropriate social media policy after losing an executive-level leader and keep online gossip and conjecture to a minimum. Expert Panel®, Forbes, 14 Apr. 2022 Some news divisions have taken pains to try and separate facts from conjecture. Brian Steinberg, Variety, 16 Mar. 2022 But journalists, particularly newsroom leaders who set the tone of coverage, should resist the temptation to hype conjecture. Brian Stelter, CNN, 28 Nov. 2021 Courts rejected challenges to the outcome as based on misunderstanding, conspiracy and conjecture. Todd Spangler, Detroit Free Press, 2 Apr. 2022 It was called the Poincaré conjecture, after the French mathematician Henri Poincaré, who’d posed it in 1904. Quanta Magazine, 9 Sep. 2021 But there is conjecture around just how organic that nickname is. Rod Mcguirk, ajc, 10 Apr. 2022 On the wild side is conjecture that the symmetrical placement of the Carnac stones occurred as the result of an alien encounter of some kind. Washington Post, 21 Jan. 2022 Recent Examples on the Web: Verb It’s not unreasonable to conjecture that some families have shifted their protein choices in response. Michael Hiltzik, Los Angeles Times, 26 Nov. 2021 Rather than allow the mind to reel and conjecture, provide information to support a valid response. Expert Panel®, Forbes, 26 Oct. 2021 Some economists conjecture that savings from the higher unemployment benefits are giving these workers some breathing room to look for better work. Michael Hiltzik, Los Angeles Times, 12 Oct. 2021 Anyone who might conjecture that Stahl is getting ready to step away from the program would be mistaken. Brian Steinberg, Variety, 8 Sep. 2021 Instead, researchers conjecture, fluvoxamine reduces inflammation. Michael Hiltzik, Los Angeles Times, 18 Aug. 2021 Cam Newton, Sam Darnold and Dak Prescott have all declined to discuss their vax status, leading to conjecture that they are not vaccinated. Elena Kadvany, San Francisco Chronicle, 9 Aug. 2021 Naturally, such a shocking death provoked rumor and conjecture about suicide or murder, which Kanigel duly reviews. Adam Kirsch, The New Yorker, 7 June 2021 In fact, linguists now conjecture that language first arose among hominids to fulfill that most fundamental of impulses: the need to lie. Bill Heavey, Field & Stream, 13 Dec. 2020 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'conjecture.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of conjecture


14th century, in the meaning defined at sense 2


15th century, in the meaning defined at transitive sense 1

History and Etymology for conjecture

Noun and Verb

Middle English, from Middle French or Latin; Middle French, from Latin conjectura, from conjectus, past participle of conicere, literally, to throw together, from com- + jacere to throw — more at jet

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The first known use of conjecture was in the 14th century

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Last Updated

22 May 2022

Cite this Entry

“Conjecture.” Dictionary, Merriam-Webster, Accessed 22 May. 2022.

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More Definitions for conjecture


con·​jec·​ture | \ kən-ˈjek-chər How to pronounce conjecture (audio) \

Kids Definition of conjecture

 (Entry 1 of 2)


conjectured; conjecturing

Kids Definition of conjecture (Entry 2 of 2)

More from Merriam-Webster on conjecture

Nglish: Translation of conjecture for Spanish Speakers

Britannica English: Translation of conjecture for Arabic Speakers


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