amp

¹ American  

[amp] / æmp /

noun

Electricity.

1. ampere.

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amp ² American  

[amp] / æmp /

noun

1. amplifier.

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verb (used with object)

1. to excite or energize (usually followed byup ).

   We were so amped up for the game that we forgot to eat.

amp ³ American  

[amp] / æmp /

noun

Slang.

1. amputation.

2. amputee.

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AMP ⁴ American  

abbreviation

Biochemistry.

1. a white, crystalline, water-soluble nucleotide, C 10 H 12 N 5 O 3 H 2 PO 4 , obtained by the partial hydrolysis of ATP or of ribonucleic acid, yielding on hydrolysis adenine, ribose, and orthophosphoric acid.

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amp. ⁵ American  

abbreviation

Electricity.

1. amperage.

2. ampere; amperes.

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amp. ¹ British  

abbreviation

1. ampere

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AMP ² British  

abbreviation

1. adenosine monophosphate

2. Australian Mutual Provident Society

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amp ³ British  

/ æmp /

noun

1. an ampere

2. informal an amplifier

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verb

1. informal to excite or become excited

AMP Scientific  

/ ā′ĕm-pē′ /

1. Short for adenosine monophosphate. An organic compound that is composed of adenosine and one phosphate group. It is one of the nucleotides present in DNA and RNA, and is also the fundamental component of ATP and ADP. During certain cellular metabolic processes, AMP forms from ADP when the latter loses a phosphate group, and AMP forms ADP by acquiring a phosphate group. Chemical formula: C ₁₀ H ₁₄ N ₅ O ₇ P.

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amp Cultural  

1. A unit of electric current (see also current). One ampere corresponds to a certain number of electrons passing a fixed point each second.

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Discover More

A typical household's electrical supply includes a total of 120 to 200 amps; a typical house circuit carries 15 to 50 amps.

Etymology

Origin of amp¹

First recorded in 1880–85; by shortening

Origin of amp²

First recorded in 1945–50; by shortening

Origin of amp³

First recorded in 1925–30; by shortening

Origin of AMP⁴

First recorded in 1950–55; a(denosine) m(ono-)p(hosphate)

Explanation

An amp is a unit of electricity. Your new air conditioner might use nine amps of power, replacing your less efficient old one. When you're measuring electrical charge or current, you can express the units in amps, which is short for amperes. Since the 1880s, the definition of amp has been "the current that one volt can send through one ohm," and the word itself comes from the French physicist who helped found the science of electromagnetism, André-Marie Ampère.

Example Sentences

To amp up tax-loss harvesting, consider a tax-optimized separately managed account.

From Barron's • Mar. 21, 2026

“I think our modern existence happens to pull from modes of interaction that really amp up the importance of mate value,” Eastwick said.

From Los Angeles Times • Feb. 12, 2026

A second danger is not paying attention to the combination of devices plugged into one extension lead, as it is easy to exceed the recommended amp limit.

From BBC • Dec. 20, 2025

You can go crazy with string lights to create an enchanted tree in your backyard or adorn it with some creepy critters — snakes, bats, spiders…you name it — to amp up the scare factor.

From Salon • Oct. 30, 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