Fragment

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A fragment is any headmate that usually does not possess full autonomy, sapience, or identity.

Fragments may come and go before fusing or growing in complexity. They may perform very specific roles, have little emotional range, or hold fractures of memory.

In the case of systems as a whole, "fragmented" or "fragmentation" (often paired with "psyche" or "sense of self") refers to traumagenic splitting.

Related Terms
Many traumagenic systems have multiple trauma holding fragments that later fuse together or into more established headmates. Headmates that are in the process of forming can be referred to as fragments too.

The term polyfragmented comes from this term, and relates to both the number of system members and the amount of fragments, specifically.

The terms centifrag, decifrag, and millifrag refer to the "size" of a fragment compared to a usual fully formed headmate.