Syssibling

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A syssibling is a headmate that is considered to be a sibling of another headmate, both from the same system or from another one. This could be symbolic or literal, or due to a source relationship.

Related Terms
Sysling, sibling figure, sysparent, parental figure, and eresian similarly describe familial relationships between headmates.

History
The term was first introduced by the Post Apocalyptic Pack