Proscriptions are collectively assumed societal regulations that insist certain behaviors are prohibited. Certain enactments are proscribed within particular groups or subgroups, whether circumscribed by race, nationality, religion, culture, peer group, even self.
For instance, it is probably looked down upon by all races to get on all fours and eat out of a dish on the floor, although my 7 year-old daughter tried this out of sympathy for our dog she thought was human.
It is probably not acceptable for a Frenchman to cheek-kiss a Norwegian. Norwegians are known for their stoicism, Frenchmen for their love of emotionally liberating wine. But, I learned right-cheek-kissing from Hispanic culture, and I do it to everybody, regardless of their culture.
Some proscriptions are stricter than others. Proscriptions are probably most important to teenagers, and can be stricter than adults for it determines top dog popularity.
Regarding myself, these days, not eating sugar is one of my proscriptions. But my not eating sugar has never been suppressed like my desire to cuss. Fortunately, it is not rigidly repressed, either, since my personal unconscious remembers how many times I have never been rigid about this particular proscription. Tonight I had ice cream at Jason’s Deli.