involving more than one country, or having power or authority that is greater than that of single countries

The United Nations is the only supernational authority that is able to solve this problem. 联合国是唯一的可以解决这个问题的多国权威机构。

Super-national control of taxation is unacceptable to many people. 对很多人来说不能接受（国家）税收由凌驾于国家之上的组织掌控。