I had a teacher that straight up said PCU inside of CPU in class. Long story short: it didn't even phase her. This, mind you, was a computer science course, AP level at the one and only highschool in a small provence of south county in the gate way to the west.
"Then the PCU takes the information and places it in the registers along with the other data waiting to be processed."
Also, I believe it's a movie title. Not sure of the relation of said definition.
Proper Condom Use
Should have taken a PCU class before I got knocked up.