"To better serve policymaking at the regional and international levels, the term “new psychoactive substances” or NPS was coined. The Commission on Narcotic Drugs introduced this term at the international level in its resolution 55/1 of 16 March 2012.
"The term 'new psychoactive substances' had been legally defined earlier by the European Union as a new narcotic or psychotropic drug, in pure form or in a preparation, that is not scheduled under the Single Convention on Narcotic Drugs of 1961 or the Convention on Psychotropic Substances of 1971, but which may pose a public health threat comparable to that posed by substances listed in those conventions (Council of the European Union decision 2005/387/JHA).
"That legal definition is now widely used and has also been adopted by the EMCDDA.18"

Source

UNODC, World Drug Report 2013 (United Nations publication, Sales No. E.13.XI.6), p. 60.
https://www.unodc.org/unodc/s…