The term 'Easing of Tension between Nations' can be summarized by the word 'Detente', which is a French term meaning the relaxation of strained relations, especially in a political context. Detente is often used to describe the period of improved relations between the United States and the Soviet Union during the 1970s. This period saw a reduction in tensions between the two superpowers, leading to increased cooperation in areas such as arms control and economic relations.