ETYM Latin postulatum a demand, request, prop. p. p. of postulare to demand, prob. a dim. of poscere to demand, prob. for porcscere; akin to German forschen to search, investigate, Skr. prach to ask, and Latin precari to pray: cf. French postulat. Related to Pray.
In logic: a proposition that is accepted as true in order to provide a basis for logical reasoning.
Necessary condition; axiom. postulant, candidate for religious order.

To take as a given; assume as a postulate or axiom; SYN. posit.