ampere

noun

am·​pere ˈam-ˌpir How to pronounce ampere (audio)
also
-ˌper How to pronounce ampere (audio)
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
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.
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

Word History

Etymology

André-Marie Ampère

First Known Use

1881, in the meaning defined at sense 1

Time Traveler
The first known use of ampere was in 1881

Phrases Containing ampere

Rhymes for ampere

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Browse Nearby Words

ampere
Ampère
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Cite this Entry

“Ampere.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ampere. Accessed 25 Mar. 2025.

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Kids Definition

ampere

noun
am·​pere ˈam-ˌpi(ə)r How to pronounce ampere (audio)
: a unit for measuring the rate of flow of an electric current

Medical Definition

ampere

noun
am·​pere
ˈam-ˌpi(ə)r also -ˌpe(ə)r
1
: the practical mks 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 equal to a constant current which when maintained in two straight parallel conductors of infinite length and negligible circular sections one meter apart in a vacuum produces between the conductors a force equal to 2 × 10−7 newton per meter of length

Biographical Definition

Ampère

biographical name

Am·​père äⁿ-ˈper How to pronounce Ampère (audio)
André-Marie 1775–1836 French physicist

More from Merriam-Webster on ampere

Nglish: Translation of ampere for Spanish Speakers

Britannica.com: Encyclopedia article about ampere

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