A semiconductor diode is a commonly used electronic device that allows the flow of current in one direction only. But what are some of the synonyms for this device? Some popular alternatives include p-n junction diode, rectifier diode, and signal diode. Another synonym for a semiconductor diode is a crystal diode, which was one of the earliest types of diodes. Zener diode and Schottky diode are two other types of semiconductor diodes that have different properties. Regardless of the name or type, all semiconductor diodes play an important role in modern electronics by regulating the flow of current and voltage.