assumption

Universal Words noun 1 [C] a belief or feeling that sth is true or that sth will happen, although there is no proof: an underlying / implicit assumption * We need to challenge some of the basic assumptions of western philosophy. * We are working on the assumption that everyone invited will turn up. * It was impossible to make assumptions about people's reactions. * His actions were based on a false assumption. * She arrived at college with a whole set of assumptions inherited from her family. 2 [C,U] ~ of sth (formal) the act of taking or beginning to have power or responsibility: their assumption of power / control * the assumption of responsibility by the government for the disaster