"Lianmeng" is the Chinese word for "alliance." But because a number of empires have used it for their title over the last two millenia, it has been colloquialized into the general term for mankind's galactic expansion.
However, when the galaxy-ruling Singularity was overthrown 250 years ago, the standing interstellar bureaucracy was fragmented into what are now called the five Lianmeng Branches: Central (which contains the Solar System), Bar, Norma, Zulu, and Deialpah (where the former capital of the empire was located).
Each is powerful in their own way, each suffered terribly after the lost of the Singularity in their own way. And each is desperate to not be taken over by any of the others.