im·po·si·tion / ˌimpəˈzishən/ • n. 1. the action or process of imposing something or of being imposed: the imposition of martial law.2. a thing that is imposed, in particular: ∎  an unfair or resented demand or burden. ∎  a tax or duty. ∎  an unsuitable addition to an artistic or other work. ∎  Christian Church the laying-on of hands, as in blessing or ordination.3. Printing the imposing of pages of type. ∎  a particular arrangement of imposed pages: some samples of 16-page impositions.

impositions. Tudor sovereigns received lifetime parliamentary grants of customs duties called tonnage and poundage, but as inflation reduced the royal revenue they had recourse to impositions—additional prerogative levies on imports, first collected under Mary I. Impositions were the subject of a legal challenge in 1606, but the court upheld the crown's right, thereby enabling James I's treasurer, Robert Cecil, greatly to expand their range and yield. The Commons never accepted the validity of these non-parliamentary levies, and they were a cause of constant friction with both James I and Charles I. They were finally declared illegal by the Tonnage and Poundage Act of 1641.

Roger Lockyer

imposition. Something laid or superimposed on, e.g., an existing building.