Clown society is a term used in anthropology and sociology for an organization of comedic entertainers (Heyoka or "clowns") who have a formalized role in a culture or society.
Sometimes clown societies have a sacred role, to represent a trickster character in religious ceremonies. Other times the purpose served by members of a clown society is only to parody excessive seriousness, or to deflate pomposity.
In the sense of how clowns function in their culture:
Members of a clown society may dress in a special costume reserved for clowns, which is often a ridiculously extreme or improper form of normal dress. Some members paint their body with horizontal black and white stripes, which represent a skeleton.
In the case of the Zuni clown society of the Pueblo Indians, "one is initiated into the Ne'wekwe order by a ritual of filth-eating" where "mud are smeared on the body for the clown performance, and parts of the performance may consist of sporting with mud, smearing and daubing it, or drinking and pouring it onto one another". The sacred clown and his apparently antisocial behavior is condoned in Indian ceremonies.
While in their costume, clowns have special permission from their society to parody or criticize defective aspects of their own culture. They are always required to be funny. Other persons living within the same culture may recognize a clown when they see one, but seldom consciously understand what the clowns do for their society. The typical explanation is "He's just a funny man."
In the case of the jester at the English Royal Court with his cap of bells and pig's bladder stick he was allowed to make fun of, be indelicate and sometimes downright rude to members of the royal family and their entourage without fear of reprisal.