A portmanteau of the two words "PSPICE Diagram." Commonly slurred together by electrical engineering students who must constantly discuss wiring diagrams with little sleep and food. Similar to liagram (Logic Diagram) or wiagram (Wiring Diagram).
Mike: "Hey Bobby, have you finished the Piagram yet for the 8 bit D/A converter circuit?"
Bobby: "Nah man I'm still working on the wiagram. Wanna order some late-night food? I haven't slept or eaten in days."
Mike: "Yea neither have I, let's do it."