What is a standard for acceptable behavior within a society called (apex)

A standard for acceptable behavior within a society is called a norm.

Explanation:

Almost every society has a series of unwritten rules on how a person should behave in a society. The rules which are acceptable to one society might not be acceptable to another society. However, a norm can be described as a way of behaviour that is considered acceptable in society. For example, shaking hands when you meet somebody is a social norm for many societies. Saying sorry when you accidentally bump into someone is also a social norm.