Term that evolved from punk anarchist usage (meaning people who knew each other enough to commit crimes together) to mainstream identity politics usage for self-segregation along race/sex/gender lines.
"The last time I heard that term, it was used by punk anarchists to mean a group of people who knew each other enough to commit petty crimes together. But now it's a bunch of idpol poisoned liberal college students and big tech workers using it to self-segregate along race/sex/gender lines."