Wiktionary
subprocess
n. A process that is part of a larger overall process.
Usage examples of "subprocess".
All that's missing is the link to the propulsion management subprocesses in their main computer.
So what's the zeroth persona at one moment can be the one-hundred-fifty-ninth tier a picosecond later, and then pop back up, and they all can spawn subprocesses and subpersonas customized to the task at hand.