Hello! So, there's a lot of terms in the plural/multiple/system community! Not just on Tumblr, but Twitter and Reddit.
We're trying our best to add as much as we can to this dictionary, for anyone to find. I know we've had trouble finding the meaning of some terms, even searching, so hopefully this will help!
Please go to the Contact page and send us a message in one of the places if we've missed something.

Disclaimer: Not all definitions are written by me, I tried to make sure everything made sense, and sometimes we aren't good at putting thoughts on paper.

All flags are above their definition.

4/6/2020: Posted, missing Member Type flags, and some System Type flags.

4/7/2020: Added another DID flag, added the remaining Member Jobs, added a few alternate names to some terms, and added some missing basic terms.

4/13/2020: Added a few terms [Parethnic, Spontagenic], added separators between flags so you can easily tell which flag goes to which definition. Added Tools section, under More.

4/19/2020: Added links to Tumblr posts for newer terms, so you can reblog and spread them. Follow the ♡'s to find the posts. Will add links for more known terms at a later date. Added relationship terms under More.

5/21/2020: Really big update.

Basic Terms

Alter : The clinical term for someone in a system.

Blurring : When two or more people are fronting, and the line between who they are gets blurred / When two people mix up a little and get blurred together.

Co-Fronting : Co-fronting or co-hosting is when two or more people are taking control of the body at once.

Co-Conscious : When two or more people are conscious at the same time. You're usually able to communicate with each other like this.

Exotrauma : Trauma that's specific to one person. Whether it's the mind trying to work through the body's trauma in chunks, or it's trauma from their source if they're an introject. This can also be trauma from other headmates, including persecutors.

Forming : When a new person is formed. Can relate to both non-voluntary, and voluntary forming. Can also be called Splitting.

Fronting : When someone is in control of the body.

Front Sticky : When someone is continuously drawn to front, no matter how many times they leave. Usually, it feels like the body wants them in control.

Front Stuck : When someone is unable to stop fronting, and is forced to keep control of the body. Unlike sticky, they can't leave front at all.

Fusion : When two or more system members fuse to become one person for a non-permanent amount of time.

Headmate : A non-clinical term for someone in a system.

Innerworld/Headspace : The innerworld, or headspace, is where headmates live inside the mind. Not all systems have headspace.

Integration : In most cases, means when system mates start fusing together permanently, usually to make a system smaller. Sometimes, it can also mean when amnesiac systems stop losing memories between each other.
This can be highly triggering for some systems, and even remind them of death. It's best to be careful on who you talk about it with.

Kin : This term is not for only systems, and it doesn't mean system. Kin are people who identify as partially or entirely nonhuman- sometimes just as another person. Whether of a fictional character, a fictional species, a non-fictional species, even another person. Kin =/= Introject. People in a system can kin, but that does not mean kinning is the same as being an introject. (See Member Types).

NPC : A non-alter/headmate in a system. Not real people, but they're filler so headspace isn't so empty.

Outerworld/Meatspace : The opposite of headspace, this is the body's world.

Parethnic : A system member who is a different ethnicity than the body.

Partner System : When two or more systems have multiple relationships between their system mates. Doesn't have to all be romantic.

Plurality/Multiplicity : The state of being plural or multiple; the name of having multiple people in one body.

Pluran : Similar to headmate, but without defining someone by their relationship to the others in their system.

Plurisex : Having different or inhuman sex characteristics because you're in a system.

Proxy : Using a Discord Bot (PK, Tupper, etc) to send a message with a webhook of yourself, or another system member relaying your message to other people.

Shadowing : Being conscious and (at least somewhat) associated with the body, but not fronting. Metaphorically looking over the fronter's shoulder.

Singlet : A non-system. One person with one body.

Singletsona : The mask everyone agrees to act as when they aren't out as a system.

Switching : When people in system switch who is fronting.

System : The collective of people or facets inside the body is (most of the time) referred to as the system.

System Hopping : When a system member "hops" from one system to another, possibly for a visit or to stay forever. While debated, it's really up to every system themselves whether they believe it or not.

System Stagnant : When the system starts to get quieter, and it’s harder for people to take front or talk to people outside of system (some even inside system). Kind of like the entire system is dissociating, and only a handful of people can really front, making them frequent fronters.

You& : A way to say "you" while acknowledging the other person is a system. Can work with other terms; I&, Me&, etc.


A note: Individual system mates can identify with these origins, just the same as systems. Not all systems like to use it for individual system mates however, so it's best not to make general statements about other systems.

Agenic : Having no origin, or not wanting to find your origin.
[no flag]

Cryptogenic : A system whose origins are unknown.


Endogenic : A system that is not formed by trauma.


Kin System : A system that forms their kins. Your kin is not a headmate, or a system, before they are formed.


Metagenic : A system with metaphysical or even spiritual origins that are not necessarily tied to any religion or practice.


Mixed Origin : See Polygenic


Multigenic : See Polygenic


Neurogenic : A system formed either by, or to help cope with, a pre-existing mental illness.

Nihilumgenic : A system that formed from nowhere, having no origin like endogenic or traumagenic or anything like that, or a system that simply as no origin, just exist for whatever reason (nihilum coming from the Latin word 'nothing’).

Pangenic : A system that has all origins.
[no flag]


Paragenic : A system caused by having Maladaptive Daydreaming Disorder, or similar experiences.

Partraumagenic / Parotraumagenic : A system formed as an intentional attempt to deal with trauma.

Pariogenic : A system that's mostly made up of walk-ins and / or soulbounds.


Parogenic : A created origin; a system in which members were purposefully created (often by an original preexisting person). Can be called Tulpamancy, but not everyone is comfortable with that.


Polygenic : A system that’s formed by multiple origins. Can be a mix of any of these. Isn't All of them.

Possessive : Systems that are formed when a spirit possesses an original, the possession is long term and is not parasitic, but instead both parties can gain something by being part of the deal.
[no flag]


Praesigenic : A fuck-you term, basically “I don’t have to tell you my system origin, that’s for me to know and for you to not make your business”.


Protogenic : A system that's been plural since birth or for as long as they can remember.


Quoigenic : The system does not know their origins or does not care about their origins.

Soulbonder : Systems in which someone is strongly attached to a character, and the character becomes a headmate.
[no flag]

Spirigenic/Spiritual : Any type of systems in which their systemhood is spiritual in some way, whether for religion, witchcraft, or other reasons.
[no flag]

Spontagenic : A spontaneously created system.

Spontaneous : A system that forms on its own, with no particular cause or event that causes it.
[no flag]


Traumagenic : A system that is formed from trauma. This does not always mean DID/OSDD, and it doesn't mean only childhood trauma.

Member Types

Different types of Headmates are around- from what jobs they have (if any), to what kind of introject they are (again, if they even are!).

Disclaimer: While we've been trying to not let any triggers get in the way of this dictionary, Jobs are too much for us to power through. While we'll write down regular jobs that come up mostly everywhere, any specific or coined jobs won't be on this list. Our mental health can barely take regular jobs, let alone more specific ones. If anyone wants to make a Job-Specific dictionary, we will gladly link it on More Reading.

Jobs And Ages

Age Forge / Age Forging : When a system member grows up mentally rather than physically in some way. They would normally act more mature and maybe take on a more caring or teenager or adult role while they’re mentally progressing.

Age Slider : Person whose age changes, or who identifies as being different ages at different times. Can sometimes be confused with Age Regression, but for a system, they're pretty much the same.

ANP (Apparently Normal Parts) : The rational, present-oriented, and grounded members that handle daily life. Mostly a DID/OSDD word.

Big : Adults in the system. Can be either 18+ or 21+, ages aren't agreed on.

Caretaker : A system member that looks after the other system members- can be only specific groups (like the Littles) or the entire system.

Co-Host : Backup or secondary hosts.

Companion : System mates that exist to keep other system mates company.

Core : The original person in a system. There's some controversy around this, and it can be violently offensive to ask about who the core is to some systems; many systems don't even have a core.

Gatekeeper : A system member that controls things, such as Fronting, access to certain areas or memories, and even access to other people. May also be an Internal Self Helper

Host : The person or people who front the most. Not all systems have a Host.

Internal Self Helper : A system member that holds knowledge about the system, alters, trauma, and/or internal workings. May or may not also be a gatekeeper

Iterive : A system member whose age is static or remains unchanging for a long period of time. Can be used as both a noun and an adjective.

Little/Syskids : Young children in a system. The ages of a Little aren't agreed on by the community either.

Lost Adults : A system member who grew up physically, but not mentally. They act less mature and possibly seem more like a little, but identify as an older age and have the image of an adult in system.

Main : Different from host, in they don’t actually have to front that much. The main people or person that everyone basically draws energy from. Usually someone that nearly everyone in system thinks of as a Main Person. There can be multiple mains.

Memory Holder : A system member that holds memories, usually traumatic ones, or even good memories about bad people. Can be Trauma Holders.

Middle/Systeen : A tween/teen in a system. Again, ages are not agreed upon, but usally 12-19~.

Perpetrator : A system member who is mean or angry to people outside of the system, mostly to keep the system safe.

Persecutor : A system member that acts out and harms other system members, or the body. Usually internalized abusive messages, and is trying in their own way to protect the system.

Both Perpetrators and Persecutors deserve love, and to know everything will be okay.

Protector : A system member who protects the body, the host, the main, other system members, and/or specific groups of members. Either by taking the abuse themselves, acting offensively to abusers, or by finding a way to get people out of the bad situation.

Sexual Alter : A system member who is possibly hypersexual, a response to abuse.

System Manager/Admin : System mates that help keep the system organized. May keep track of headmates, medications, appointments, etc.

Trauma Holder : A memory holder, specifically for Trauma.

Introject Types

An Introject is a system member that either comes from an outside source, or is based on an outside source.

Aesthetive : an introject of an aesthetic personified (eg cottagecore, clowncore, vaporwave, etc)

Amitive : An introtive/Introject of a member of another system.

Armistive : A fuck you term, means that you don’t need to know if the person is a fictive/factive/fucktive/fogtive/fuzztive/etc.

Clusterject : When you’re an introject of a bunch of abstract thoughts thrown into one person (A few sentences or hyperfixations basically tossed into a pot and stirred together to make one person). Being an introject of a bunch of small things rolled into one.

Demi- : Partially a (fictive, factive, etc).

Fableing : A fictional identity facet in a median system, who has experiences and feelings in common with both fictives and fictionkin in a way that makes them feel positioned somewhere between or adjacent to the two.

Factive : An introject of a real person.

Faitive/Fucktive/Fcktive : An introject that’s somewhere between/a mix of a fictive and factive. [♡]

Fictive : An introject from a fictional source.

Fogtive : Someone who is partially, somewhat, or almost a factive, but factive doesn't seem ‘quite right’ or ‘entirely accurate’. Between or partially factive and something else (the something else may or may not be defined, personal choice).

Fuzztive : Someone who is partially, somewhat, or almost a fictive, but fictive doesn't seem ‘quite right’ or ‘entirely accurate’. Between or partially fictive and something else (the something else may or may not be defined, personal choice).

Kinform : A kintype that became a headmate.

Multi- : Being multiple introjects at once, either being formed as multiple, or accepting the other identities into yourself later. Ex. Multi-fictive, Multi-factive, Multi-identity.

Musicative : A plural system introject that comes from a song, music video, band, etc. A pluran in a system whose identity is a song [etc]. [♡]

Objective : Also Objtive. An objective is a headmate that is either based on or formed as an object.

Parative : An introject of a para in your daydreams.

Pre- : A person in a system who was not originally an introject, but feels like they are becoming one, or that an introjected identity is relevant and meaningful to them.

Somtive : An introject from a night dream.

Spiritive/Myctive : An introject from a religious or spiritual source.

Now-PC : A previously-NPC that’s now a person in the system. Someone who had previously been filler in your system, and now is an actual sentient person in system.

Member Origins and Misc

Extranthrope : A nonhuman member in a multiple system. Can be shortened to “extranth.” [♡]

Facet : Distinct personalities within the same person.

Fragment : A person that isn't fully formed, yet may still exist.

Multi-Identity : Having multiple identities at once; unlike being a Median System, they are all you at once instead of multiple facets.


Previme : A parame that became a headmate.


Prevera : A para that became a headmate.

Servitor : Thoughtforms that are created to carry out specific tasks or jobs. They are typically not sentient and usually require a source of energy to continue functioning.

Soulbond : People that come into system permanently, similar to gateway.


Textform : A headmate created by role-play, writing or acting until they gain free will.

Thoughtforms : A headmate one forms/creates inside a system until they gain free will. Can also be called Parogenes and Tulpas. Not everyone is comfortable with all of these terms.

Walk-ins : A system member who simply shows up in the system out of the blue, fully-formed. Can be fictive, factive, or neither.

System Types

Other than Origin, there's system types that go even further than that.

Aerogenic System : Alters that are directly related to the environment around them, or
system members that form due to weather conditions or environmental conditions.

Aquatien System : A system that is stagnant like a shallow pool of water, but still grows (eg. in members).


Bombo / Bombogenic System : System member count explodes rapidly, or a system that fuses older alters (not permanently) to form newer ones, which are, in turn, fragmented again.


BPD System : A system caused by BPD. Under Neurogenic.

Cryogenic System : A synonym for quoigenic, where it seemingly comes out of nowhere, or like its coming from the “cold”; a system that seems to have frozen before (dormancy) and is now “thawing” (multiple alters) or vice versa; a system that flows between the above definition consistently due to things such as trauma or neurodivergence; a system that feels like it goes dormant in certain “seasons” or periods experienced by the body; etc.


DID System : Dissociative Identity Disorder, or DID, is a dissociative disorder characterized by multiple separate personality states, amnesia, and dissociation.

Diversian : Medians who are closer to the plural side of the spectrum.


Dreamway System : Dreamway systems are for neuronarrators/people with maladaptive daydreaming (MaDD)/similar experiences. Essentially like a gateway system, except the "outside source" you have connection to/with are that of your daydreams world/s, and the people that walk in are paratives (headmates formed from MaDD/similar experiences)

Faciogenic System : A subsystem made up of created headmates (thoughtforms).
[idk where the flag is]


Gateway System : “Systems where system members have their own physical or spirit bodies from another world [including the inner world]“ OR “ Systems that have a gateway/connection to another universe in their system, that members can enter and exit through“

Kinegenic System : A system where the front changes often, to the point of multiple headmates fronting a day, not all at the same time.
[idk where the flag is]

Mesosian : Medians who are in or around the middle of the spectrum.


Orbit System : A system that has a central body in which alters revolve in cycles ; alters are set to a certain time of day when they front ; or
alters front only rarely, and wait for all other system mates to front before fronting again

Origin-flux : The original way the system was formed differs from the way the majority of currently present headmates have formed since the system's assumed origin.
[idk where the flag is]


OSDD-1a and -1b : OSDD-1 is “almost DID,” but lacking one of the diagnostic criteria for it. OSDD-1a is DID without sufficiently distinct alters, whereas OSDD-1b is DID without amnesia.

Parasian : Medians who are closer to the singlet side of the spectrum.


Phytogenic : A system that constantly divides other system members up, and fuses them back together after a while, or constantly divides in general.


Pyro : A once small system of only a few headmates and a host that had a large influx of headmates enter into the headspace ; a once large system of many headmates that lost a large portion of the alters to dormancy or something else ; a system that has many alters that fluctuate in and out of dormancy ; or
a system that never has a stable amount of alters at one time

UDD/USDD : USDD is diagnosed when a dissociative disorder is present but does not fully meet the criteria for DID, DPDR, dissociative amnesia, or one of the OSDDs. USDD may also be used when the clinician does not choose to disclose more information about the dissociative disorder being diagnosed or is diagnosing quickly in emergency settings
[no flag]

Växer System : A system where all the headmates grow older each year as the body grows a year older.
[idk where the flag is]

System Structure

Adaptive : A system that changes and forms to adapt to their environment.

Architecture: Complex : Large/complex systems, including polyfragmented+, fractal, and multi-layered.

Architecture: Median / Median System : Part of the spectrum of singular and plural. One person made up of multiple facets. Being neither multiple nor singlet. A system where boundaries between members are less defined, and may see themselves as all originating or being part of the same person.

Architecture: Plural : A system of multiple people.

Architecture: Singular : One person with one body; a singlet.

Communication: External only : Communication is external, through a system journal, a discord server, etc.

Communication: Internal conflicts : Fighting/arguing between members.

Communication: Internal only : Members communicate internally, or via headspace.

Communication: Mixed : Both internal and external communication.

Communication: Poor skills : Poor communication skills between members.

Fractal : Every member is a complex and every changing subsystem. The system moves/copies their parts around, and fully remixes members sometimes.

Inner World: Absent : No headspace or inner world.

Inner World: Active : Headspace is active all the time, or exists as a parallel world of some kind.

Inner World: Passive : Headspace is only active while the fronter looks/focuses on it.

Inner World: Restricted : Access to headspace is restricted, for some/all members.

Knowledge: Managed : Access to knowledge is controlled/managed, like by a gatekeeper.

Knowledge: Mixed : A mix between Shared and Restricted.

Knowledge: Restricted : Knowledge is unique to each member.

Knowledge: Shared : Knowledge is shared between members/switches.

Layers : Different levels of a system, where different headmates live in different layers. Layers may or may not know (of) each other.

Memories: Managed : Access to memories is controlled/managed, like by a gatekeeper.

Memories: Mixed : A mix between shared/segregated.

Memories: Poor Recall : Memory is poor in general, like due to disorders/physical condition.

Memories: Segregated : Amnesia between members/switches.

Memories: Shared : Memories are shared between members/switches.

Mixed System : A system with both median and multiple parts (not to be confused with Mixed Origin System.) A system that is a mix between median and multiple.

Polyfaceted : A median system of 100+ facets.

Polyfragmented : A system with 100 headmates or more. These types of systems are also known for having multiple subsystems and layers. These kinds of systems have fragments, as well.

Polymultiple : A multiple system of 100+ full members. The difference between these and Polyfragmented, is Polymultiple don't have fragments.

Polyplural : A general term for any type of system with 100+ members.

Subsystem : A headmate with their own system; a system within a system.

Switching: Managed : Fronting/switching is controlled and managed, like by a gatekeeper.

Switching: Mixed : A mix between reactive and voluntary.

Switching: Reactive : Most switches are reactions, or triggered.

Switching: Voluntary : Most switches are voluntary, or controlled.

System MOGAI and Systems Only Terms (Some Shared With Kin)

Carrd only allows 100 elements without a paid account [plus this section would take forever anyways], so here's the Plural MOGAI wiki, and some System MOGAI Tumblrs (please contact me if you want to be listed on this page).

Plural MOGAI Wiki


More Plurality Websites

Since this is only a dictionary, here's some more websites for further reading.

System Sources


Specifically for Plurality

Blossom : A plurality glossary in the form of a Discord Bot. It also can give cute system-related messages.

Pluralkit : A Discord bot to send messages with system members' own pictures and names. Also has a website to edit system member profiles easier. Disclaimer: Non-Systems are allowed to use it for RP, kinshifts, etc.

Switch Calendar : A switch tracker that uses Pluralkit's API to show your system's switches.

Tupperbox : Another Discord bot to send messages with system members' own pictures and names. Much simpler, with no Switches or Member Profiles. Disclaimer: Non-Systems are allowed to use it for RP, kinshifts, etc.

Tools Systems May Find Useful

Picrew : An avatar maker. Good for making system member pictures.

Flowcharty : A tool that lets you put options with traits, then answer questions to figure out who is fronting.


Aepluric : A relationship where all members are involved (pairs, constellations, or as a group, etc.). Not every relationship has to be romantic.

Intuspluric : Relationships and attractions within a system.

Partner System : Two systems in a relationship. Doesn't have to be romantic.

Plurillean : A member of a system who is attracted to other members of their own system. This doesn’t have to be exclusive, and you can love both system members, and non-system members.

Plush System : A queerplatonic partner system.

Polypluric : A relationship with a system that is, or feels, polyamorous. Can also be called Sorpluric.

SMLSM : System Mate loving System Mate. A member of a system loving members of their own system.

Squish System : A platonic partner system.

Sysian / Sysmasexual : A member of a system who is only attracted to other members in their own system. This is exclusive.

Ultipluric : Relationships and attractions between systems.

Unpluric : In a relationship with a system in a way that seems monogamous, possibly with a median system.


Please contact us for any of the following:

^ We missed something, and you know the meaning.
^ You've coined a term and want it on the dictionary.
^ You've made a flag and want it added. Even if the term already has a flag, more flags are welcome.

Shoot either an Ask or a DM :)