a proposition, or set of propositions, set forth as an explanation for the occurrence of some specified group of phenomena, either asserted merely as a provisional conjecture to guide investigation (working hypothesis) or accepted as highly probable in the light of established facts.

a proposition assumed as a premise in an argument.

the antecedent of a conditional proposition.

a mere assumption or guess.

noun

calcualtion , measurement , proof , reality , truth

noun

antecedent , apriority , assignment , assumption , attribution , axiom , basis , belief , conclusion , condition , conjecture , data , deduction , demonstration , derivation , explanation , foundation , ground , guess , inference , interpretation , layout , lemma , philosophy , plan , position , postulate , premise , presupposition , principle , proposal , proposition , rationale , reason , scheme , shot in the dark * , speculation , starting point , suggestion , supposition , surmise , system , tentative law , term , theorem , thesis , theory