1.  conjecture(n = noun.cognition) speculation - a hypothesis that has been formed by speculating or conjecturing (usually with little hard evidence); "he dismissed it as mere conjecture"; "speculations about the outcome of the election"
Derived form adjective conjectural₁, verb conjecture₁

2.  conjecture(n = noun.communication) guess, hypothesis, speculation, supposition, surmisal, surmise - a message expressing an opinion based on incomplete evidence;
Derived form adjective conjectural₁

3.  conjecture(n = noun.cognition) - reasoning that involves the formation of conclusions from incomplete evidence;
Derived form adjective conjectural₁, verb conjecture₁

   conjecture(v = verb.cognition) hypothecate, hypothesise, hypothesize, speculate, suppose, theorise, theorize - to believe especially on uncertain or tentative grounds; "Scientists supposed that large dinosaurs lived in swamps"
Derived form noun conjecture₁, noun conjecture₃
Sample sentences: They %s that there was a traffic accident

   An opinion, or judgment, formed on defective or presumptive evidence; probable inference; surmise; guess; suspicion. [1913 Webster]

   To arrive at by conjecture; to infer on slight evidence; to surmise; to guess; to form, at random, opinions concerning. [1913 Webster]

   To make conjectures; to surmise; to guess; to infer; to form an opinion; to imagine. [1913 Webster]

conjecture, n. & v.
--n.
1 a the formation of an opinion on incomplete information; guessing. b an opinion or conclusion reached in this way.
2 a (in textual criticism) the guessing of a reading not in the text. b a proposed reading.
--v.
1 tr. & intr. guess.
2 tr. (in textual criticism) propose (a reading).

Derivative:
conjecturable adj.

Etymology:
ME f. OF conjecture or L conjectura f. conjicere (as com-, jacere throw)

N  supposition, assumption, assumed position, postulation, condition, presupposition, hypothesis, blue sky hypothesis, postulate, postulatum, theory, thesis, theorem, data, proposition, position, proposal, presumption, divination, conjecture, guess, guesswork, speculation, rough guess, shot, shot in the dark, conjecturality, surmise, suspicion, sneaking suspicion, estimate, approximation (nearness), inkling, suggestion, hint, intimation, notion, impression, bare supposition, vague supposition, loose supposition, loose suggestion, association of ideas, (analogy), metonym, metonymy, simile (metaphor), conceit, idea, thought, original idea, invention (imagination), supposing, given, mooted, postulatory, assumed, supposititious, suppositive, suppositious, gratuitous, speculative, conjectural, hypothetical, theoretical, academic, supposable, presumptive, putative, suppositional, suggestive, allusive, if, if so be, an, on the supposition, ex hypothesi, in the case, in the event of, quasi, as if, provided, perhaps, for aught one knows.

VB  suppose, conjecture, surmise, suspect, guess, divine, theorize, presume, presurmise, presuppose, assume, fancy, wis, take it, give a guess, speculate, believe, dare say, take it into one's head, take for granted, imagine, put forth, propound, propose, start, put a case, submit, move, make a motion, hazard out, throw out a suggestion, put forward a suggestion, put forward conjecture, allude to, suggest, hint, put it into one's head, suggest itself, run in the head, marvel if, wonder if, wonder whether.