So poligamia is actually polygamy, which in a traditional sense is all about a male marrying multiple wives. So I don't ever like to refer to this as polygamy because I believe in sexual equality and I'm certainly not interested in collecting wives. Polyamory is, simply put, a relationship structure where both sides agree to have certain rules that allow you to have partners that are either outside of the core relationship, or actually a part of the core relationship. For instance, you could bring another person into your relationship and then you would have what's called a "triad". There's so many ways to approach poly but yeah, just wanted to give you the heads up there so you're not confused as to what it is!
Thanks so much for sharing @elchicoausente!