polyfidelitous describes a relationship in which three or more people treat one another as equal partners and agree to keep sexual and romantic 📝intimacy closed within the group, admitting new members only by the 📝consent of everyone already in it.
The adjective derives from polyfidelity — Greek poly (many) joined to Latin fidelitas (faithfulness) — and names a structure of many partners bound by a single, shared fidelity. It sits under the 📝Consensual Non-Monogamy (CNM) umbrella but differs from most open forms of 📝polyamory in where it draws the line of exclusivity: around the whole group rather than around a couple. A polyfidelitous group is closed the way a monogamous couple is closed, only larger.
The term was coined in the 1970s by the 📝Kerista Commune in San Francisco, which organized its members into egalitarian, closed intimacy circles and paired the word with 📝compersion, the joy taken in a partner's other bonds. Two features define the arrangement: equality, since no partner is ranked above another, and collective rather than dyadic fidelity, since the group itself is the unit of commitment. Those traits set it apart from hierarchical or non-exclusive polyamory, where partners may rank their relationships or keep forming new ones independently.