Polycule is a complex polyamorous relationship, usually with five or more people involved. This relationship could be a complex layout, a group relationship, a line relationship, and/or possibly a multiamorous relationship.
Flag
The polycule flag was coined by beyond-mogai-pride-flags on August 15th, 2018.
Resources
https://beyond-mogai-pride-flags.tumblr.com/post/177013716430/polycule-a-network-of-non-monoamorous
Etymology
The term is a portmanteau of poly- and molecule, in reference to the complex shapes of some molecules.