Monogamy Anyone?

Unicorn- A bisexual woman who has sex with hererosexual married couples

So-So- Your significant other's significant other.

Throuple- A couple plus one

Solo Poly-having more than one partner but no "main parter"

Anchor partner- The person you've been with longest and may live with.

Open relationship - A committed relationship between two partners who also sleep with other people but may have to get permission in advance.

Polyamory- The practice of maintaining intimate relationships with multiple committed partners.