This is a collection of common plural community terminology that I am aware of.

General

• Headmate
• Headspace
• Layer
• Origin
• Plural
• Role
• Side system
• Source
• Subsystem
• System

System origins

• Adaptive
• ADHDgenic
• Agenic
• Autigenic
• Cryptogenic
• DID
• Endogenic
• Neurogenic
• OSDD
• Parogenic
• Traumagenic
• Tulpamancy
• Xenogenic

System types and functions

• Blackout
• Blending
• Blurring
• Coconscious
• Cofronting
• Dissociation
• Final fusion
• Fronting
• Frontstuck
• Fusion
• Grayout
• Integration
• Internal communication
• Median
• Mediple
• Memory sharing
• Multiple
• Partitionary
• Passive influence
• Singlet
• Splitting
• Switching
• Syscovery
• System-hopping
• Time loss

Headmate sources and roles

• Autoject
• Big
• Body
• Core
• Facade
• Facet
• Factive
• Fictive
• Fragment
• Fronter
• Gatekeeper
• Gestalt
• Host
• Insider
• Internal self-helper
• Introject
• Little
• Memory-holder
• Middle
• Original
• Part
• Persecutor
• Protector
• Self
• Thoughtform
• Trauma-holder
• Tulpa

Syscourse

• Fakeclaiming
• OEA
• RAMCOA
• SRA
• Syscourse
• Sysmed
• System exclusionist
• Traumascum

Not all of this terminology necessarily applies to me personally, but I'm writing about it here anyway for the utility of doing so. That said, please be aware that despite my best efforts to be inclusive, I am only one person—well, only one human being, anyway—and my telling of these concepts is inherently biased.

I'm aware some of these terms are controversial. (They will be marked as such on their respective pages.) Including a term in this glossary doesn't mean I endorse it, only that I'm aware of it.

(Actually, all of this terminology is controversial, unfortunately, because of system exclusionists. But that controversy will not be documented per-page. Otherwise every single page in this namespace would have a controversy section, and anyway, it's not an attitude that I want to speak for any more than necessary.)