Wafer
Wafer turns up in 2 fields: valves, electronics. Here is what it means to the people in each one.
Wafer in valves
A thin valve body clamped between two pipe flanges by long bolts passing outside it.
Wafer butterfly and check valves have no flanges of their own and are centered by the bolts or locating holes. They are light and cheap, but if one side of the line is unbolted the valve is no longer held. Lug-style bodies solve that by giving each bolt its own threaded hole, so the valve can hold pressure with the downstream pipe removed.
"Don't use a wafer there, when we pull the strainer that valve has to hold the header, get a lug body."
Wafer in electronics
A highly polished slice of semiconductor material used as the foundation for fabricating integrated circuits.
A wafer is a thin, perfectly flat disk sliced from a cylindrical ingot of monocrystalline silicon or other semiconductor material like gallium arsenide. It undergoes multiple stages of photolithography, doping, and etching to build hundreds or thousands of individual chips on its surface. Once fabrication is complete, the wafer is diced into individual units for packaging.
"The fab just scrapped an entire 300mm wafer because of a misalignment in the photolithography stepper."