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

Prices are also benefiting from restocking demand by cathode producers before the Lunar New Year holiday, he says.

From The Wall Street Journal • Feb. 11, 2026

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

From The Wall Street Journal • Dec. 2, 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

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