What are the teams named after?

Most teams are named after their leader, others have a common developer (FN, AR), but the rest have a meaning completely unknown to me. Palette, 404, and DEFY, also ATK, FlashDel, and Puzzle if you count the event squads, must have some deeper significance. Maybe 404 is for HK weapons that had less than total adoption by the Bundeswehr, hence are not found? I can't even guess about the others, can anyone enlighten me?

And this is before getting into the faction names; what is Sangvis Ferri, 90wish, KCCO, Paradeus (semi-god?), and Griffin and Kryuger itself (GK instead of HK?) supposed to mean?