Hypothesis

1. (n.) A supposition; a proposition taken for granted, in order to draw a conclusion or inference for proof of the point in question; something not proved, but assumed for the purpose of argument, or to account for a fact or an occurrence; as, the hypothesis that head winds detain an overdue steamer.

2. (n.) A tentative theory or supposition provisionally adopted to explain certain facts, and to guide in the investigation of others; hence, frequently called a working hypothesis.

Thesaurus Entries

a priori principle, affirmation, apriorism, assertion, assumed position, assumption, axiom, basis, categorical proposition, conjecture, data, first principles, foundation, ground, guesswork, hypothesis ad hoc, inference, lemma, major premise, minor premise, philosopheme, philosophical proposition, position, postulate, postulation, postulatum, premise, premiss, presumption, presupposal, presupposition, proposition, propositional function, set of postulates, speculation, statement, sumption, supposal, supposing, supposition, surmise, theorem, theory, thesis, truth table, truth-function, truth-value, working hypothesis