Describes a
launch vehicle that is built by strapping together existing components, such as
booster rockets or additional stages. It is a reference to the Kerbal Space Program, "create and manage your own space program", which allows players to build custom rockets in exactly that
way.
"I would say that of all the new vehicles described here, the
Omega is easily the most kerbal since it's just a bunch of parts strapped together." (Scott Manley, "New Glenn,
OmegA and Vulcan Get Air Force Approval", YouTube, October 11,
2018, 6:38.)