The Meaning of Conjecture: What It Is and How To Use It

Do you know the definition of conjecture? This article will provide you with all of the information you need on the word conjecture, including its definition, etymology, usage, example sentences, and more!

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What does the word conjecture mean?

According to Cambridge Dictionary of the English Language and Merriam-Webster Unabridged English Dictionary, the word conjecture is a noun that refers to some guess that was based on how something seems, and not based on proof. An example of this could be when scientists use incomplete evidence or little hard evidence as the means by which to come to a formation of conclusions. Conjecture means the expression of an opinion rather than the assembling of facts. This can also be used as a verb to refer to the action of making said guess. Something that is an unproven idea could be said to be pure conjecture or mere conjecture. This word is often used to call out when someone is spewing information as if it is fact, when in reality there is no verifiable evidence to back it up. 

There are many different examples of conjecture. For example, a physicist at Princeton University could use a few pieces of available evidence to assert that large dinosaurs are still alive and living in swamps based on the trajectory of subatomic particles. However, there is not enough hard evidence to back this up. Therefore, it could be considered conjecture. When people call the outcome of the next election before all of the results are tallied, this is considered conjecture. There are various conjectures that are presented by mathematicians and scientists all of the time until they are proven. These can also be called hypotheses. These theorems and hypotheses, such as the Riemann Hypothesis or Fermat’s last theorem, are important for studying mathematical history as well as new areas of mathematics. People attempt to find disproof or to reject these propositions to advance knowledge.

Many different languages also contain words that mean conjecture. You may notice that some of these words look and sound similar to the word conjecture. These are called cognates, which are words and phrases that look, sound, and mean the same thing between languages. These are often formed when two words have the same root or language of origin, such as Latin or Greke. This list of translations of conjecture is provided by Word Sense.

  • Mandarin: 臆測‎, 臆测‎ (yìcè), 推測‎, 推测‎ (tuīcè)
  • Norwegian Nynorsk: gjetting‎ (fem.), gissing‎ (fem.)
  • Greek: εικασία‎
  • Japanese: 推測‎ (すいそくる, suisoku)
  • Serbo-Croatian: pretpostavka‎ (fem.), nagađanje‎ (neut.)
  • German: Vermutung‎ (fem.), Verdacht‎ (masc.), Mutmaßung‎ (fem.)
  • Czech: dohad‎ (masc.)
  • Dutch: gissing‎ (fem.), giswerk‎ (neut.), conjectuur‎ (fem.)
  • Norwegian Bokmål: gjetning‎ (common), gjetting‎ (common), gjettverk‎ (neut.), antakelse‎ (masc.), formodning‎ (common)
  • Russian: предположе́ние‎ (neut.), дога́дка‎ (fem.)
  • French: conjecture‎ (fem.)
  • Maori: pūmāramarama‎
  • Finnish: arvelu‎, arvaus‎, olettamus‎, otaksuma‎
  • Italian: congettura‎
  • Bulgarian: предположение‎ (neut.)
  • Romanian: ipoteză‎, presupunere‎ (fem.)
  • Spanish: conjetura‎ (fem.), suposición‎ (fem.), especulación‎ (fem.), teoría‎ (fem.)
  • Scottish Gaelic: tuairmse‎ (masc.), barail‎ (fem.), tomhas‎ (masc.)
  • Portuguese: conjetura‎ (fem.), conjectura‎ (fem.)
  • Swedish: förmodan‎ (common)

How can the word conjecture be used in a sentence?

The word conjecture can be used in many different circumstances to refer to some opinion, judgment, or assumption that is made not on proof, but on how something seems. In this example, Riley’s teacher has accused him of cheating on a test.

Teacher: You missed all of the same problems as Troy. He scored ten percent higher than he usually does, and he was sitting right next to you. How am I not meant to believe you let him cheat off of you?

Riley: Because that’s all conjecture! You have no proof! I have never cheated before, and never plan to. How do you know he wasn’t sneaking glances at my paper?

What are synonyms and antonyms for the word conjecture?

There are a plethora of different words that have the same meaning as conjecture. These are called synonyms, and can be used interchangeably with the word conjecture. Synonyms are useful words to know because they are an easy way to expand your vocabulary, as well as a good tool to avoid repeating yourself. This list of synonyms for the word conjecture is provided by Thesaurus.

  • cogitation
  • supposition
  • postulate
  • assumption
  • belief
  • opinion
  • induction
  • reflection
  • presumption
  • estimate
  • review
  • meditation
  • cerebration
  • guesstimate
  • thought
  • shot in the dark
  • notion
  • fancy
  • hypothesis
  • deliberation
  • hunch
  • brainwork
  • sneaking suspicion
  • shot
  • prediction
  • theorizing
  • judgment
  • theory
  • feeling
  • reckoning
  • studying
  • conclusion
  • deduction
  • ballpark figure
  • consideration
  • supposal
  • stab
  • postulation
  • weighing
  • inference
  • view
  • stab in the dark
  • speculation
  • surmise
  • guess
  • surmisal
  • thinking
  • thesis
  • guesswork
  • contemplation
  • presupposition
  • divination
  • suspicion
  • perhaps
  • excogitation

There are also many different words that mean the opposite of the word conjecture. These are called antonyms, and are another great, easy way to work on expanding your vocabulary. This list of antonyms for the word conjecture is provided by Thesaurus as well. 

  • establishment
  • certainty
  • principle
  • evidence
  • perfection
  • corroboration
  • plain talk
  • appearance
  • bottom line
  • case
  • lowdown
  • reason
  • dope
  • basis
  • information
  • goods
  • smoking gun
  • permanence
  • score
  • truthfulness
  • attestation
  • gospel
  • solidity
  • reasons
  • scene
  • whole story
  • brass tacks
  • scripture
  • infallibility
  • credentials
  • rectitude
  • matter
  • affidavit
  • exactitude
  • straight stuff
  • authenticity
  • warrant
  • concrete happening
  • picture
  • why
  • scoop
  • data
  • naked truth
  • palpability
  • record
  • genuineness
  • testament
  • inside track
  • gospel truth
  • facts
  • clue
  • intelligence
  • stability
  • cue
  • fact
  • verity
  • honest truth
  • factualism
  • veracity
  • whyfor
  • certitude
  • actuality
  • accuracy
  • nitty-gritty
  • truism
  • rightness
  • certification
  • witness
  • wherefore
  • criterion
  • trace
  • maxim
  • grabber
  • demonstration
  • what’s what
  • testimony
  • legitimacy
  • precision
  • experience
  • substantiality
  • validation
  • correctness
  • averment
  • verisimilitude
  • argument
  • substantiation
  • exactness
  • unvarnished truth
  • law
  • grounds
  • how it is
  • documents
  • factuality
  • proof
  • skinny
  • factualness
  • confirmation
  • paper trail
  • deposition
  • axiom
  • trueness
  • verification
  • clincher
  • like it is
  • exhibit
  • chapter and verse

What is the origin of the word conjecture?

According to Etymonline, the word conjecture has been used since the late 14th century to refer to some interpretation of signs or dreams, as well as some supposing or surmising. This word comes from the Old French or Middle French conjecture meaning surmise or guess. This may also come directly from the Latin coniectura, meaning some conclusion, guess, or inference. This literally means some casting together. The Latin coniectūra comes from the Latin coniectus, from the perfect passive participle of cōniciō, meaning “to throw together.” This comes from the root com meaning together and the root iacere meaning to throw and is of Proto-Indo-European roots. This word has been used to mean some unverified act since the 1520s and to refer to the act of forming an opinion with no proof since the 1530. The word conjecture has been used as a verb since the early 15th century, and has parallels to the Middle English conjecte and conjecten. Related words include conject (an intransitive verb or transitive verb), conjectured, and conjecturing.

Overall, the word conjecture refers to some inference of opinion that was formed without sufficient evidence or facts to back it up. This word comes from the Latin conjectūra and is often used to call out when someone is attempting to spew unverified facts, such as the outcome of the election or another proposition. Try using this word of the day in a sentence today!