Is devoted to definitions of basic sociological concepts 'society' and 'social'. The paper reviews briefly academic literature stressing opposite formulations often contradicting formal logic. In authors' opinion generic notion in defining 'society' and 'social' should be seen in activity-exchange concept that links individuals into a sort of wholeness to determine features and social essence of both termini. This is an arguable confirmation for the fact that society is not only a self-describing subject but also a self-preserving one. Qualitative contrasts are emphasized of activity-exchange from other kinds of interaction (emotional, communicative, legal etc.) that do shape other forms of social systems (community, association, state, population). Building on these postulations, authors define the notion of 'society' stressing generic notion and essence of the notion of 'social'. Their point of view aims to embrace into notions of society and social concrete enough ideas and unambiguously researched objects.