If you’re a birder, Virgo, or expecting parent, odds are you’re familiar with nesting—aka the process of preparing and inhabiting a home. Outside of binocular-laden bird watching and astrological deep-dives, the term nesting is commonly used amongst polyamorous and other non-monogamous folks with the word partner tacked onto the end.

“Nesting partners are two or more people who agree to own a house or rent an apartment together,” explains Ally Iseman, a non-monogamy sexpert and founder of Passport 2 Pleasure, a concierge wellness guide for couples and individuals exploring healthy non-monogamy. Basically, nest partners are just two partners who live together.

It sounds simple enough, and in many cases it is simple. Given how different cohabitation looks (and feels) for ENM compared to monogamous folks, however, sometimes people are left with the wrong impression, or just downright confused, when they learn their recent right swipe, co-worker, or family member has a nesting partner.

Part of the confusion comes down to the differences in expectations and norms between monogamous and non-monogamous relationships, says Iseman. Think about it: In the vast majority of monogamous relationships, the partner you choose to live with is also the person with whom you split finances, share a bed, have sex, raise children, and so on. “In nesting relationships, none of these other dynamics are an implied [guarantee],” she says. “People could be nesting partners and simply live under the same roof but have separate bedrooms, only see each other occasionally, and not share finances, for example.”

Because the term “nesting partner” divorces cohabitation from the other elements often implied when romantic partners decide to live together, odds are you have questions. Below, everything you need to know about nesting partners, including what makes them different from regular ‘ole roommates, anchor partner, primary partner, and more.

Nesting partner, explained

As mentioned earlier, a nesting partner is the name for a partner with whom you decide to live, explains Leanne Yau, the educator behind Poly Philia, a social media project dedicated to education and entertainment on polyamory, non-monogamy, and personal growth. “The term doesn’t imply anything more or less than that you are partners, and also that you cohabitate.”

According to Yau, the term likely originated in the 1961 book Stranger in a Strange Land by Robert Heinlein. (In the novel, an alien comes to Earth and starts a trend of communal living where everyone lives in groups called nests.) “A lot of people in the polyamorous community are big fans of that book and took the concept of nesting from its pages,” Yau says.

These days, Yau says the term can be used by non-monogamous and monogamous folks alike. But most commonly, it’s used by people who are polyamorous with multiple loving partnerships and are looking for language that accurately describes their current relationship standings, obligations, and entanglements. “People who are polyamorous like to be very specific in their language in order to properly differentiate their partners from one another, as well as explain those particular relationships,” they say.

“If you have multiple partners, some who you live with and some who you don’t, you have to consider the boundaries of your nesting partner when making dates, doing sleepovers, if you hang at your house, and so on.” —Leanne Yau, founder, PolyPhilia

Wait, how is this different from having a roomie?

Glad you asked. When two (or more) individuals are nesting partners they are, well, partners. “The term nesting partner typically suggests that the individuals living together currently have a romantic and/or sexual relationship with one another,” says Yau. (Though, sometimes the partnership between nesting partners is of the co-parenting or queerplatonic variety).

Meanwhile, the term “roommate” does not imply or suggest that the people living together are partners of any variety, says Iseman. She says being roommates typically entails a platonic relationship—meaning there is no romantic or sexual relationship between these cohabitants. “Regular roommates likely wouldn’t take one another into account when making decisions about their individual finances, job offers, dating pool, the way nesting partners might,” she says.

To be clear: If a drunken night lands you and your roommate(s) in the same bed, you don’t automatically transform from roommates into nesting partners. Nested partnership is an intentional decision, says Yau, while banging a roommate in this way is usually an oopsy-daisy.

Nested partner vs. primary partner vs. anchor partner

Again, many folks who are polyamorous lean on a wide variety of modifiers in order to describe their partnership relationships, commitments, and entanglements. While this language can be clarifying for those who are in-the-know on polyamory lingo, for everyone else it can be cause for a head-scratch. Unfortunately, such is commonly the case with nesting partners, which Yau says is commonly confused with the terms like “primary partner” and “anchor partner” (despite not being synonymous at all).

Primary partner implies a hierarchy that nesting partner does not

The term primary partner is used to denote that one particular partner is the most significant, important, and/or considered partner in an individual’s life, explains Yau. “They’re your top dog,” they say.

“When someone has a primary partner, they are naming that they are practicing a form of polyamory known as hierarchical polyamory,” says Iseman. In practice, these additional partners generally receive less from the individual in question financially, emotionally, and time-wise, compared to the primary partner. (Note: While people typically only have one primary partner, they might have two or three if they are in an established triad or quad, which are three- and four-person relationships.)

However, Iseman says that people who choose to nest with one (or more) of their partners are not inherently practicing this branch of polyamory. “It’s possible for someone to have a primary partner who they do not nest with, and also possible to have a nesting partner who they do not consider primary,” she says.

If you’re an outsider to a relationship, grasping this difference is essential for understanding the particular dynamic(s) at play—assuming that those dynamics are something you have the right to understand. Being cognizant of this difference can also help you figure out what question(s) to ask to determine whether or not a potential-partner is available to the type of partnerships you are interested in.

Anchor partners do not necessarily live together

Much as an anchor offers security to a boat, helping it combat wind and currents, an anchor partner is a steadfast person you can rely on throughout life’s ups and lows. “You can think of your anchor partner(s) as the other co-star(s) or another main character(s) in your story in addition to you,” says Iseman. As the parentheticals imply, it is possible to have more than one anchor partner.

“Your anchor partners are the people who emotionally anchor, or support, you,” says Yau. “They are the partners who feel like home even if you do not literally share a home.” When anchor partners share a home they are called anchor partners and nesting partners, not one or the other.

Now, the exact role anchor partners play in one another’s day-to-day lives can vary, based on a variety of things such as whether or not they are they are practicing hierarchical polyamory, live together (aka are also nesting partners), live in the same town or far away, and so on, notes Iseman. Regardless of the daily interactions, however, there’s an assumption that the relationship will stay steady and secure for a long, long time.

“If you are in a romantic relationship and you choose to live together, society tends to see you as a more ‘legitimate couple.'” —Leanne Yau

The pros and cons of nesting with someone while polyamorous

Moving in together can offer people in non-monogamous relationships many of the same benefits monogamous folks hope to obtain by shacking up. To name a few: Reduced cost of living, increased time together, greater access to a partner type of companionship, greater ease with co-parenting kids or pets, and the general joys of living with someone important to you. But there are additional benefits, as well as some challenges that are unique to polyamorous practitioners.

“If you are in a romantic relationship and you choose to live together, society tends to see you as a more ‘legitimate couple,’” says Yau. That’s a very frustrating reality (that we’re not endorsing), but Yau notes that there are various social benefits that can come along. For example, you might be more apt to receive a plus-one invite to a wedding, for instance, or your more traditional (read: mononormative) family may finally start to acknowledge the relationship for the importance it has long held. “There are also safety benefits as the unfortunate statistical reality is that living alone, especially as a woman, is less safe than when there is at least one other person sharing the residence,” adds Iseman.

That said, there may be potential challenges of nesting with someone while also dating—or having the option to date—others. “If you have multiple partners, some who you live with and some who you don’t, you have to consider the boundaries of your nesting partner when making dates, doing sleepovers, if you hang at your house, and so on,” says Yau.

While some people will be totally okay if you have sex in common spaces or in a shared bedroom, Yau says, others might prefer that dates happen when they are not there, or that other partners never come over at all. If you and your nesting partner are not on the same page about this, there is a high likelihood of conflict. One person, for example, might feel like the safety and sanctity of their home is being violated if they allow sleepovers with someone’s other partners, while one person might feel that their autonomy is threatened if they feel like they can’t host other partners.

Choosing to nest with one partner and not another can also cause confusion, jealousy, resentment, or other types of sadness to your other partners that aren’t going to nest with you. The cultural script teaches us that moving in with is an elevation of and intensification of that relationship that moves it one step higher on the relationship escalator, notes Yau. Being a partner not invited into that step can feel personal or disappointing, even when that isn’t the case, they say.

Communication is the key for a happy, healthy nested relationship

You might have read all this and gotten really nervous about the potential of having a nesting partner. But here’s the good thing: Most of the potential tension points that can arise as a result of choosing to nest together can be navigated with communication, communication, and more communication.

Generally, it’s best to talk with your potential future nesting partner about boundaries, dating ground rules, and more before the U-haul has been called.

In addition to talking about things all cohabitors should talk about (cleanliness and chores, platonic pal and/or party hosting, and sleep schedules), Yau says potential nesters should ask one another the following questions:

• What does home mean to you?
• Can we have non-sexual dates in the home? What about sexual dates?
• What might sleepovers with other partners look like moving forward?
• What places in the home are okay or off-limits for sex?
• How do you feel about being home when another one of my partners is present?
• What kind of post-sex or post-date rituals or chores do we need to put into place for the sake of comfort and cleanliness?

Obviously, an individual’s answers can (and probably will!) evolve through experience and exposure to different situations. But having these convos ahead of time can help you determine if you’re compatible nesters.

As for navigating other (non-nested) partners’ potential jealousy, Yau notes it can be helpful to explicitly name the fact that nesting can be a practical rather than emotional decision. They say it’s also a good idea to brainstorm other ways to show any other partners just how important they are to you. Some examples: with a ceremony, jewelry, friend or family integration, planned vacation(s), photos on social media, or adding them as an emergency contact.

All in all, understanding what a nesting partner is can be helpful for clarifying what your current relationship set-ups are, and what you dream them to become. “The term can allow you to more specifically explain and name your past, current, and future entanglements,” says Yau.

But as in the case with most identity labels (see: queer, non-monogamous, asexual, etc.) “nesting partner” means and implies something slightly different to the different people using it. So, when it’s appropriate, it’s best to ask educated follow-up questions when someone uses the term to describe their own relationship, and to invite others to inquire further when you’re using the term.