mores

mores \MOR-ayz; -eez\, plural noun:

1. The fixed customs of a particular group that are morally binding upon all members of the group.
2. Moral attitudes.
3. Customs; habits; ways.

Usually the laws mirror the mores of the populace in this regard, though at times they run ahead, and at times they lag behind.
-- Daniel C. Maguire, "Death Legal and Illegal", The Atlantic, February 1974

In much the same bold spirit, I rapidly absorbed the other gestures, turns of phrase and exclamations popular among my peers, as well as grasping the deeper mores and etiquettes prevailing in my new surroundings.
-- Kazuo Ishiguro, When We Were Orphans

Artists rebelled against the stodgy mores of the bourgeoisie.
-- David Brooks, "The Organization Kid", The Atlantic, April 2001

Mores comes from Latin, plural of mos, "custom." It is related to moral.