"Postulational" is a complex word that relates to the act of making a hypothesis or assumption as the starting point for an argument or theory. Some synonyms for postulational include speculative, conjectural, theoretical, suppositional, and hypothetical. All of these words imply that the stated position is based on an assumption or speculation rather than concrete evidence. Other words that might be used in place of postulational include propositional, conjectural, speculative, and hypothesized. In academic or scientific settings, it's important to use precise language and to know what different words mean in order to communicate effectively and avoid ambiguity.