diode

Noun	1.	diode - a thermionic tube having two electrodes; used as a rectifier Synonyms: rectifying tube, rectifying valve
	2.	diode - a semiconductor that consists of a p-n junction Synonyms: crystal rectifier, junction rectifier, semiconductor diode

(hardware, electronics)

diode - A semiconductor device which conducts electric current run in one direction only. This is the simplest kind of semiconductor device, it has two terminals and a single PN junction. One diode can be used as a half-wave rectifier or four as a full-wave rectifier.

electron tube, rectifying tube, rectifying valve, thermionic tube, thermionic vacuum tube, thermionic valve, tube, vacuum tube