Definitions by Baba O'Reilly

PSW 

Initialism for Program Status Word:
A computer's hardware register that maintains the status of the program being executed.

Under z/VM:
If the PSW is not shown in any message, display it by entering: #cp d psw

CP D PSW
PSW = 030E0000 810591B0

PSW by Baba O'Reilly January 24, 2008