Definition of assumption

• a statement that is assumed to be true and from which a conclusion can be drawn; "on the assumption that he has been injured we can infer that he will not to play"
• a hypothesis that is taken for granted; "any society is built upon certain assumptions"
• the act of taking possession of or power over something; "his assumption of office coincided with the trouble in Cuba"; "the Nazi assumption of power in 1934"; "he acquired all the companys assets for ten million dollars and the assumption of the companys debts"