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