plural amperes
1
: the practical meter-kilogram-second unit of electric current that is equivalent to a flow of one coulomb per second or to the steady current produced by one volt applied across a resistance of one ohm
2
: the base unit of electric current in the International System of Units that is defined by setting the fixed numerical value of the elementary charge to 1.602176634 x 10-19 ampere seconds
Examples of ampere in a Sentence
a current of 15 amperes
Recent Examples on the Web
Many Bissell vacuums have around 9 amperes of power, although some are as high as 12.
—
Bestreviews, Chicago Tribune, 18 Mar. 2025
One hundred amperes is equivalent to the electrical service provided to many households.
—David Wallace, CBS News, 14 May 2024
For a large generator, this can amount to thousands of amperes.
—Benjamin Kroposki, IEEE Spectrum, 13 Apr. 2024
The rate of flow is measured in amperes: 1 amp = 6.24 x 1018 electrons flowing through a certain point per second.
—Rhett Allain, WIRED, 23 Feb. 2024
The unit of electric current known as the ampere, or amp for short, is named after the founder of electrodynamics.
—IEEE Spectrum, 11 July 2023
The digital circuit breaker is also about 3,000 times as fast as most mechanical breakers, enabling circuit interruption capabilities up to 150,000 amperes, the upper limit for today’s circuit breakers.
—IEEE Spectrum, 20 June 2023
But Mudawar, who has previously collaborated with Ford Motor Co., is developing a system that would use special cooling technology to get more than 2,400 amperes—1,400 amperes of current would put five-minute EV charging within reach.
—Rebecca Heilweil, Smithsonian Magazine, 24 May 2023
Right now, researchers think that faster-charging EVs would need charging cables that can handle far more amperes—the unit for electric current—than what vehicles can handle today.
—Rebecca Heilweil, Smithsonian Magazine, 24 May 2023
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Bestreviews, Chicago Tribune, 18 Mar. 2025
One hundred amperes is equivalent to the electrical service provided to many households.
—David Wallace, CBS News, 14 May 2024
For a large generator, this can amount to thousands of amperes.
—Benjamin Kroposki, IEEE Spectrum, 13 Apr. 2024
The rate of flow is measured in amperes: 1 amp = 6.24 x 1018 electrons flowing through a certain point per second.
—Rhett Allain, WIRED, 23 Feb. 2024
The unit of electric current known as the ampere, or amp for short, is named after the founder of electrodynamics.
—IEEE Spectrum, 11 July 2023
The digital circuit breaker is also about 3,000 times as fast as most mechanical breakers, enabling circuit interruption capabilities up to 150,000 amperes, the upper limit for today’s circuit breakers.
—IEEE Spectrum, 20 June 2023
But Mudawar, who has previously collaborated with Ford Motor Co., is developing a system that would use special cooling technology to get more than 2,400 amperes—1,400 amperes of current would put five-minute EV charging within reach.
—Rebecca Heilweil, Smithsonian Magazine, 24 May 2023
Right now, researchers think that faster-charging EVs would need charging cables that can handle far more amperes—the unit for electric current—than what vehicles can handle today.
—Rebecca Heilweil, Smithsonian Magazine, 24 May 2023
Cite this Entry
“Ampere.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ampere. Accessed 31 Mar. 2025.
Copy CitationKids Definition
ampere
noun
am·pere
ˈam-ˌpi(ə)r 
: a unit for measuring the rate of flow of an electric current
Biographical Definition
Love words? Need even more definitions?
Merriam-Webster unabridged
Share