cathode

American  

[kath-ohd] / ˈkæθ oʊd /

noun

1. the electrode or terminal by which current leaves an electrolytic cell, voltaic cell, battery, etc.

2. the positive terminal of a voltaic cell or battery.

3. the negative terminal, electrode, or element of an electron tube or electrolytic cell.

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cathode British  

/ kæˈθɒdɪk, -ˈθəʊ-, ˈkæθəʊd, kæˈθəʊdəl /

noun

1. the negative electrode in an electrolytic cell; the electrode by which electrons enter a device from an external circuit

2. the negatively charged electron source in an electronic valve

3. the positive terminal of a primary cell

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cathode Scientific  

/ kăth′ōd′ /

1. The negative electrode in an electrolytic cell, toward which positively charged particles are attracted. The cathode has a negative charge because it is connected to the negatively charged end of an external power supply.

2. The source of electrons in an electrical device, such as a vacuum tube or diode.

3. The positive electrode of a voltaic cell, such as a battery. The cathode gets its positive charge from the chemical reaction that happens inside the battery, not from an external source.

4. Compare anode

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Other Word Forms

• cathodal adjective

Etymology

Origin of cathode

1825–35; < Greek káthodos a way down, equivalent to kat- cat- ( def. ) + hodós way

Compare meaning

How does cathode compare to similar and commonly confused words? Explore the most common comparisons:

• anode vs. cathode

Example Sentences

During testing, the hydrated version held nearly twice as much charge as standard sodium-ion cathode materials.

From Science Daily • Feb. 19, 2026

It expects average production of about 100,000 tons of cathode annually over 22 years.

From The Wall Street Journal • Dec. 2, 2025

When fully operational, Taseko expects Florence to annually produce 85 million pounds of cathode.

From The Wall Street Journal • Dec. 2, 2025

The Department of Energy terminates a grant for a battery cathode grade lithium hydroxide manufacturing facility.

From Barron's • Oct. 16, 2025

Except for the hum of the green cathode tube, it's quiet.

From "Things Not Seen" by Andrew Clements