See conjecture in Webster's New World Roget's A-Z Thesaurus II
noun
Abstract reasoning:
speculation, theory. See belief, thoughtsA judgment, estimate, or opinion arrived at by guessing:
guess, guesswork, speculation, supposition, surmise. See opinion
verb
To draw an inference on the basis of inconclusive evidence or insufficient information:
guess, infer, speculate, suppose, surmise. See opinion
Learn more about conjecture