1. The negative electrode in an electrochemical cell or vacuum tube, from which electrons are emitted or toward which positive ions move.
Usage: Also spelled 'cathode' (more common in modern usage).; Technical term used in physics and chemistry.

Examples

• In a battery, electrons flow from the kathode to the anode through an external circuit.
• The kathode of a vacuum tube emits electrons when heated.
• During electrolysis, positive ions are attracted to the kathode.
• X-ray tubes rely on electrons produced at the kathode.
• The kathode and anode are the two main terminals in an electrochemical cell.