The Narrowing of Median
Multiple (adj.): Two or more identities/people in the same body.
Midcontinuum (adj.): Any plural experience that does not fit under multiple or singlet.
A Brief History of Median
The term "median" goes back quite a ways. The concept was coined by the Vickis around 1996 under the word midcontinuum, along with the idea of a dissociative continuum between non-dissociative singlets and multiples. Eventually the term became "median" thanks to Pavillon's Library in order to include systems that did not experience pathological dissociation, as the previous term was strongly linked to the concept of a dissociative continuum and therefore excluded those that did not dissociate but still considered themselves plural.
Here's the original definition of midcontinuum, taken from The Wonderful World of the Midcontinuum:
"Everyone dissociates. At one end of the dissociative continuum is 'normal' or 'common' dissociation that nearly everyone engages in, such as daydreaming, highway hypnosis or other forms of spacing out, or getting lost in a book. At the other end are the behaviors that characterize 'classical' multiples, who may have large numbers of very distinct insiders with little internal communication, serious difficulties with time loss, amnesia, and so on.
"Between these two extremes, there is a lot of gray. Ranging from having different 'roles' that you live out in different situations, to having an 'inner child' or 'inner children' with varying degrees of separateness, to having 'ego states', 'parts' or 'fragments' that don't seem to be whole people, to having some but not all of the diagnostic criteria for what is now known as DID, Dissociative Identity Disorder (formerly MPD, Multiple Personality Disorder)."
Midcontinuum was intended to encompass a very wide range of experiences, and median followed in its footsteps, though with the change in terminology came some narrowing of the definition.
"We prefer to use median to describe anyone who feels they are more than one but not a group of completely independent persons, particularly if the group feels that they all originate and rely upon a central or original person," wrote the coiner (emphasis ours). That specification was not present before, and it quickly caught on.
Nowadays, median is typically used to describe one very specific experience of plurality: having a central, shared identity composed of semi-individual parts or facets, typically all reliant on a core self. When someone refers to their system as median, the assumption in many plural spaces is that there is minimal separation and a particular experience of plurality in which there is a single person divided into parts. It's rare that one sees the word used to refer to other experiences that do not quite fit under multiple or singlet, and I feel that much of its purpose as an umbrella or spectrum term has been lost.
Multiple (adj.): A type of system where the members are fully separated and distinct.
Median (adj.): A type of system where the members are not fully separated and/or distinct, but are still more separate than a singlet's parts; that is, any experience of selfhood and identity that does not fit under multiple or singlet. Usually means "one person with independent facets/parts."
Mixed System (adj.): A system where some parts of the system are multiple, and others are median.
The Trouble with Labels
Communication is a two-way street. I can ramble on about something for as long as I'd like, but if you don't understand my words in the way I intended them, then the communication has failed. Similarly, labels matter, and the definitions of those labels changes how people view one another. "Geek" used to be an insult, but now it's taken on a more benign connotation as someone who is passionate about something (typically media). Calling someone a bastard used to be one of the most serious insults you could give them, but now the word falls alongside mild swear words and certainly isn't something the average person would kill someone to preserve their honor over. When a label is used in one sense and interpreted in another, there's a communication problem. If someone calls you a geek as an insult and you interpret it as a simple statement that you like media, then something has clearly gone wrong.
There is a place for the expansive definition of median. I've met more than a handful of systems that did not feel they fit into the definition of multiple, but who were still decidedly plural. Some of those systems were made of parts that were all the same person or relied on a central identity. Some of them were not. I've seen systems call themselves median because they had overlaps in identity but were otherwise separate, were made of fragments with no individual identities, were different versions of the same template identity, blended often, didn't lose time but were still separate, and all sorts of other experiences. It's quite the diverse group. The problem arises when others see that label of median and assume that their experience is one of "parts of a single, central person" when it is something else entirely. At that point, the label is no longer serving its purpose. This happens often with "median." The term is ceasing to be an umbrella and is beginning to describe one very specific experience of plurality instead.
The plural community places an almost fanatic emphasis on labels (which is a whole other problem). You're expected to know your origins, functioning, system type, structure, and more. All of these things have associated labels that people are usually expected to use in order to fit in and interact with others like them, and it's increasingly difficult to find spaces where it is not the norm to share at least one label related to one's system type and/or structure. With this sort of emphasis on labels, having one that suits you is important. There's a reason that there are so many words coined by the community. There's a need to have a word for everything. Even outside of the plural community, labels are useful tools for understanding one's experiences.
What happens when the one word you have to explain your experiences is changed in such a way that you can no longer use it, particularly in communities where labels are nearly essential? If a system is not separate enough to feel comfortable calling themselves multiple but is too separated to fit under singlet, median would have easily encompassed their experiences in the past. The word covered a diverse range of plural experiences and allowed those in the gray areas of identity to describe themselves. That is increasingly no longer the case. As the definition of median continues to narrow to describe a single experience of plurality rather than the spectrum it was intended to describe, people will be left without words to describe their experiences for themselves and others. People have already begun trying to fill this gap with words such as mediple, monoconscious, mesosian, parasian, and so on, and the spectrum of experiences between singlet and multiple is becoming increasingly divided as a result. This division drives some people to feel excluded or unwelcome, while others feel compelled to fit definitions that don't match their experiences at all.
Multiple (adj.): A type of system where the members are fully separated, highly individualized, fully elaborated, and have no fuzziness or overlap in identity whatsoever. Often associated with severe amnesia and disordered functioning, and occasionally toted as the only "real systems."
Median (adj.): One person composed of multiple facets or parts. Typically assumed to be either OSDD-1a or a weirdly segmented singlet, and seen as "not plural enough" by some or looked down upon.
Mixed (adj.): A system that's multiple but has a median subsystem, or a median system that interacts with others as multiple, or some weird blend of median and multiple that people just treat like a multiple system. Oftentimes, the median parts are minimized or ignored in favor of the visibly multiple parts of the system.
Exclusion of Diversity
Umbrella labels exist for a reason. Specific labels are wonderful for those that fit them, but by the nature of specific labels, not everyone will align with them. Umbrella labels fill in the gaps between and beyond specific labels, ensuring that fringe experiences are as welcome as normative ones. They allow a community to thrive by welcoming diversity. To create a truly accepting, inclusive, and supportive community, it's important that umbrella labels be available for those that need them.
Median was originally an umbrella label for a wide range of experiences, but it no longer is. I cannot count the number of times I've run into systems who believed they could not call themselves median because they did not share a common self or have a central person. These systems often wanted to be referred to as median and did not fit the paradigms of multiple or singlet, but the increasing specificity of the median definition led them to feel excluded from the label. As a result, many of these systems have felt that no label described them, something that can be quite distressing in a community built on labels. It's become common belief that median only refers to systems that identify as a single person made of parts or facets, not to systems that are elsewhere on the spectrum between singlet and multiple, and this is to the detriment of those that do not fit the narrowed definition. They're often left feeling as though they don't have a place in the community because their experiences are not reflected there.
As time goes on, the plural community's labels seem to become more and more specific and polarized. "Multiple" used to refer to any system, regardless of structure, before taking on the connotation of being entirely separate people. "Median" used to encompass everyone that was neither singlet nor multiple, and now refers to a single experience within that gray area. Rather than addressing the root issue of definitions narrowing to the point of excluding those that used to use them, more and more labels are being coined to fill the gap, and these labels are themselves narrowing. There's a runaway train in the plural community of hyper-specific labelling without the existence of true umbrella labels, to the detriment of everyone. It's all too easy to force oneself to fit the closest word and hope that's good enough to belong.
Multiple (adj.): A system where the members are, or wish to be seen as, two or more separate people.
Median (adj.): Any experience of plurality that does not fit under multiple or singlet.
Mixed (adj.): A system that has some median components and some multiple components.
We Need an Umbrella
When we create umbrella labels, people are brought together and given space to be themselves. "Plural" describes an incredibly wide array of experiences, and it's allowed for discussion among wildly different systems that would otherwise never meet or share their thoughts. The word doesn't expect anyone to have a particular experience so long as they're more than one in some way. It embraces individual differences. This embrace of diversity has allowed many systems to explore themselves and share what they've learned with the wider community, to the benefit of all. It's allowed people to find others that understand them. This alone shows how powerful a good umbrella label can be when it comes to community and empowerment.
We need median to be an umbrella again. There are a lot of systems that don't fit the definitions of multiple or singlet, and many of these systems have been pushed out of the one word that used to describe them. They've been left without a term to share their experiences under, without a way to find others like them. This is harmful to an inclusive community that supposedly welcomes diverse experiences and gray areas. Not having a label to look for makes it harder to find others to relate to, harder to describe one's experiences to others, and harder to feel like one belongs in the community in the first place. For some, it drives them out of considering themselves to be plural at all because they see no one like them and no words that accomodate them. It's difficult to feel accepted when no one acknowledges you.
There's a lack of resources and discussions about median experiences in the plural community, perhaps partially because so many medians have been excluded by language and hyper-specificity. When you have no words to describe yourself, it's hard to share who you are. We need more median voices to be heard, but the language and discussions don't leave space for them. I've seen people tell each other that they're not really median because they're not one person. I've seen people tell medians that they're not plural at all because "everyone has parts." It's difficult to share one's experiences if everyone tells you you're not allowed to describe them the way you always have.
Bringing back the wider definition of median gives these systems recognition and acceptance in the community. It enables them to define themselves instead of trying to adhere to not-quite-right specific definitions, and it allows their individual experiences to shine. We need to make the plural community more comfortable for those that don't fit the multiple paradigm. Widening median's definition to include diverse experiences again is a good first step.