Sentence:  Before [Martyn] Frampton published his book "Legion of the Rearguard", an exhaustive examination of the <WSD>dissidents</WSD>, he highlighted sections of it released in a report by the International Center for the Study of Radicalisation (ICSR) at w:King's College London 
Meaning of the word marked with <WSD> tags:  A person who formally opposes the current political structure, the political group in power, the policies of the political group in power, or current laws.