The article addresses some dynamic processes in the terminology of such knowledge as PR-studies, or the science of public relations. The terminology of public relations is an open system. The formation of the public relations terminology system has been focused by various social and humanistic sciences: philology, sociology, philosophy, advertising studies, the theory of mass communications and journalism. New terms "communication product" and "media product" are introduced into the scientific framework. It is noted that the emergence of new media leads to the formation of new terms that denote the actors of modern public online communications, carriers and textual results of their activities.