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

  • noun Opinion or judgment based on inconclusive or incomplete evidence; guesswork.
  • noun An opinion or conclusion based on guesswork.
  • intransitive verb To judge or conclude by conjecture; guess.
  • intransitive verb To make a conjecture.

from The Century Dictionary.

  • noun The act of forming an opinion without definite proof; a supposition made to account for an ascertained state of things, but as yet unverified; an opinion formed on insufficient presumptive evidence; a surmise; a guess.
  • noun Suspicious surmise; derogatory supposition or presumption.
  • noun Synonyms Supposition, hypothesis, theory.
  • To form (an opinion or notion) upon probabilities or upon slight evidence; guess: generally governing a clause.
  • Synonyms Imagine, Conjecture, Surmise, Guess, Presume, fancy, divine. Imagine literally expresses pure speculation, and figuratively expresses an idea founded upon the slightest evidence: as, I imagine that you will find yourself mistaken. Conjecture is something like a random throw of the mind; it turns from one possibility to another, and perhaps selects one, almost arbitrarily. Surmise has often the same sense as conjecture; it sometimes implies a suspicion, favorable or otherwise: as, I surmise that his motives were not good. Guess suggests a riddle, the solution of which is felt after by the mind—a question, as to which we offer an opinion, but not with confidence, because the material for a judgment is confessedly insufficient. To presume is to base a tentative or provisional opinion on such knowledge as one has, to be held until it is modified or overthrown by further information.
  • To form conjectures; surmise; guess.

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

  • transitive verb To arrive at by conjecture; to infer on slight evidence; to surmise; to guess; to form, at random, opinions concerning.
  • intransitive verb To make conjectures; to surmise; to guess; to infer; to form an opinion; to imagine.
  • noun An opinion, or judgment, formed on defective or presumptive evidence; probable inference; surmise; guess; suspicion.

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

  • noun formal A statement or an idea which is unproven, but is thought to be true; a guess.
  • noun formal A supposition based upon incomplete evidence; a hypothesis.
  • noun mathematics, philology A statement likely to be true based on available evidence, but which has not been formally proven.
  • noun obsolete Interpretation of signs and omens.
  • verb formal, intransitive To guess; to venture an unproven idea.

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

  • verb to believe especially on uncertain or tentative grounds
  • noun reasoning that involves the formation of conclusions from incomplete evidence
  • noun a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence)
  • noun a message expressing an opinion based on incomplete evidence


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

[Middle English, from Old French, from Latin coniectūra, from coniectus, past participle of conicere, to infer : com-, com- + iacere, to throw; see yē- in Indo-European roots.]

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin coniectūra ("a guess"), from coniectus, perfect passive participle of cōniciō ("throw or cast together; guess"), from con- ("together") + iaciō ("throw, hurl"); see jet. Compare adjective, eject, inject, project, reject, subject, object, trajectory.


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