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

One big problem is that China dominates the battery supply chain, accounting for 99% of cathode supply for LFP batteries, according to Hughes.

From The Wall Street Journal • Mar. 19, 2026

In July, Beijing said it would require licenses to transfer certain technologies linked to lithium-ion battery manufacturing overseas, and in October it started requiring export licenses for certain manufacturing equipment and cathode materials.

From The Wall Street Journal • Nov. 5, 2025

"The thicker the cathode is, the theoretical energy density of the battery -- the amount of energy being held within a specific area -- improves," Oh said.

From Science Daily • Oct. 17, 2025

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

From Barron's • Oct. 16, 2025

They had discovered the X ray, the cathode ray, the electron, and radioactivity, invented the ohm, the watt, the Kelvin, the joule, the amp, and the little erg.

From "A Short History of Nearly Everything" by Bill Bryson