This study sought to propose a redefinition for the concept of folksonomy from the identification and analysis of the characteristics, relationships and impacts of the post-truth as a phenomenon in the knowledge organization. The methodology used was based on an exploratory and qualitative investigation that was composed by the integration between the bibliographic research and the terminographic approach. It presents as focus of analysis a corpus made up of 120 articles published in the period from 2005 to 2021 in an international scope. Its results made it possible to characterize the phenomenon of post-truth and its implications in the field of knowledge organization; made possible a reflection on the theoretical and methodological bases that establish folksonomies as knowledge organization systems, which culminated in the understanding of folksonomy as an algorithmically directed mode of manifesting and imposing meanings and discourses based on the relational structures provided by the sociotechnical networks in digital context.