mores

tavat A set of moral norms or customs derived from generally accepted practices rather than written laws.
1970, Alvin Toffler, Future Shock, Bantam Books, page 99:

All of us seem to need some totalistic relationships in our lives. But to decry the fact that we cannot have only such relationships is nonsense. And to prefer a society in which the individual has holistic relationships with a few, rather than modular relationships with many, is to wish for a return to the imprisonment of the past — a past when individuals may have been more tightly bound to one another, but when they were also more tightly regimented by social conventions, sexual mores, political and religious restrictions.

It is relevant here to recall that the word “morality” is derived from mos with its plural mores, and that in its present usage it has not lost this connexion with the mores — the rules of behaviour — of a society.