This could also help you out a bit: Glossary and Definitions
Dyad - a relationship between two people within a poly arrangement
For example, my polycule is a Vee, and there are three dyads:
- me + CJ - we are married (with romance and sex and all that)
- me + Mark - we are romantically and sexually involved with each other
- CJ + Mark - they are in friendly terms, not involved with each other romantically or sexually
Triad - a relationship with three people where everyone is romantically involved with each other
Quad - a poly arrangement with four people, most often two pre-existing couples who "couple up" together.