posit, contend, premise, postulatum, suppositum, presumption, premiss, presupposer, presupposition, postulator, more...

conjecture, hypothesis, theorem, lemma, corollary, axiom, more...

fundamental, first, basic, second, parallel, fifth, necessary, third, general, moral, mere

form of an axiom,   assumed proposition,   assumes as fact,   geometric premise,   assumed truth,   true assumption,   belief assumption,   plausible premise,   it can be held that,   axiom base