ul·ti·ma ra·tio \|u̇ltəməˈräd.ēˌō; |əltəməˈrāshēˌō, -āˌshō\noun Etymology: New Latin : the last or final argument : the last resort (as force) < impaired by methods in which violence is the ultima ratio — New Republic > < the strike is the ultima ratio of Trade Unionism — Hewlett Johnson >