Fragment

A member of a system who isn't a complete person or is not a fully formed person. A fragment may one day become a complete person, remain the way they are, or even disappear. They may be a piece of another person, part of a median system or subsystem, a chunk broken/split off another person, etc.

Servitors are generally thought to be fragments/shards. Members of a median system or subsystem are sometimes called aspects or facets, but almost never fragments or shards.