From Pluralpedia, the collaborative plurality dictionary
syshopgenic (adj.)
Applies tosystems, headmates

Syshopgenic is an origin when a member of a system travels to a singlet, causing the singlet to become plural.

This could be from the system member who traveled going over to the singlet and staying, or it could be that their presence caused the singlet to form a system.

Related Terms

System Origin - The way a system forms - the way specific headmates form; may apply to one or more members

System Travel - also referred to as System Hopping; when a headmate leaves their original system to join a new system temporarily or permanently

Adoptive - A headmate that system hops permanently