Describes the practice of having more than one committed, loving, sexual relationship at the same time. All of the partners involved in the relationship are aware and consenting of every other partner.
There are many variations of polyamorous relationships including triad, vee, quad, polyandry, polygyny and many others. The common ingredient between the relationships being that all parties are consenting and non-monogamous.
Nick is polyamorous; he has multiple committed relationships. Each partner is aware of the others, and he has varying levels of emotional and sexual intimacy with each.