The article presents and analyzes selected basic problems coinciding with the issues of the inclusion and integration of population into the domain of social security, and it answers the research question: what is the proper, complete and exact meaning of the notions of security, social security, and social welfare? Critical semantical analysis of many works and statements, from classical to modern to newest ones, is the principal research method. According to the central conclusion, the most proper definition of social security identifies it with care, protec-tion and control and not mainly with the absence of threats. The author underscores that leading publications identify social security with protecting the existential foundations of ...