Lineage from Daito ryu and technical curriculum are both totally culturally contextual
"Physics" is either universal, or also culturally contextual.
Everything is culturally contextual. That doesn't really address what I'm saying, though.
What I am saying is that, contrary to what Christian asserted, it's possible for a definition of aikido to be non-universal without using setting, mode of dress, or social customs as criteria. A definition of aikido based on lineage, physical principles, and technique is still functional and still non-universal.