To be classed as an unmutual meant a citizen would be shunned by other citizens until he conformed or became "mutual." If that didn't work, other citizens would eventually take it upon themselves to correct the unmutual's behavior with increasing levels of violence.
Can be used as a noun, adjective, or insult.
"Fox News considers any reporter on their staff engaging in honest journalism to be an unmutual."
ADJECTIVE: "Talk show host Bill O' Reilly routinely engages in unmutual behavior when shouting down people with opposing viewpoints."
INSULT: "Unmutual! UNMUTUAL!"