buffer

¹ American  

[buhf-er] / ˈbʌf ər /

noun

1. an apparatus at the end of a railroad car, railroad track, etc., for absorbing shock during coupling, collisions, etc.

2. any device, material, or apparatus used as a shield, cushion, or bumper, especially on machinery.

3. any intermediate or intervening shield or device reducing the danger of interaction between two machines, chemicals, electronic components, etc.

4. a person or thing that shields and protects against annoyance, harm, hostile forces, etc., or that lessens the impact of a shock or reversal.

5. any reserve moneys, negotiable securities, legal procedures, etc., that protect a person, organization, or country against financial ruin.

6. buffer state.

7. Ecology. an animal population that becomes the prey of a predator that usually feeds on a different species.

8. Computers. a storage device for temporarily holding data until the computer is ready to receive or process the data, as when a receiving unit has an operating speed lower than that of the unit feeding data to it.

9. Electronics. a circuit with a single output activated by one or more of several inputs.

10. Chemistry.

    1. any substance or mixture of compounds that, added to a solution, is capable of neutralizing both acids and bases without appreciably changing the original acidity or alkalinity of the solution.

    2. Also called buffer solution.  a solution containing such a substance.

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verb (used with object)

1. Chemistry. to treat with a buffer.

2. to cushion, shield, or protect.

3. to lessen the adverse effect of; ease.

   The drug buffered his pain.

4. Digital Technology. to temporarily save (data) before actively accessing it so that it can be loaded at a rapid or uniform rate: You’ll get a load screen while the game buffers those high-resolution graphics.

   Give the app time to buffer the audio when you are streaming music.

   You’ll get a load screen while the game buffers those high-resolution graphics.

buffer ² American  

[buhf-er] / ˈbʌf ər /

noun

1. a device for polishing or buffing, as a buff stick or buff wheel.

2. a worker who uses such a device.

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buffer ³ American  

[buhf-er] / ˈbʌf ər /

noun

British Slang.

1. a foolish or incompetent person.

2. a fellow; man.

3. a chief boatswain's mate in the British navy.

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buffer ¹ British  

/ ˈbʌfə /

noun

1. informal a stupid or bumbling man (esp in the phrase old buffer )

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buffer ² British  

/ ˈbʌfə /

noun

1. any device used to shine, polish, etc; buff

2. a person who uses such a device

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buffer ³ British  

/ ˈbʌfə /

noun

1. one of a pair of spring-loaded steel pads attached at both ends of railway vehicles and at the end of a railway track to reduce shock due to contact

2. a person or thing that lessens shock or protects from damaging impact, circumstances, etc

3. chem

   1. an ionic compound, usually a salt of a weak acid or base, added to a solution to resist changes in its acidity or alkalinity and thus stabilize its pH

   2. Also called: buffer solution.  a solution containing such a compound

4. computing a memory device for temporarily storing data

5. electronics an isolating circuit used to minimize the reaction between a driving and a driven circuit

6. short for buffer state

7. informal to finish or be stopped, esp unexpectedly

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verb

1. to insulate against or protect from shock; cushion

2. chem to add a buffer to (a solution)

buffer Scientific  

/ bŭf′ər /

1. Chemistry A substance that prevents change in the acidity of a solution when an acid or base is added to the solution or when the solution is diluted. Buffers are used to make solutions of known pH, especially for instrument calibration purposes. Natural buffers also exist in living organisms, where biochemical reactions are very sensitive to changes in pH.

2. Computer Science A device or an area of a computer that temporarily stores data that is being transferred between two machines that process data at different rates, such as a computer and a printer.

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buffer Cultural  

1. In chemistry, the components of a solution that can neutralize either an acid or a base and thus maintain a constant pH.

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Discover More

Buffers are often used in medications designed to decrease acidity in the stomach.

Other Word Forms

• unbuffered adjective

Etymology

Origin of buffer¹

First recorded in 1825–35; buff ² + -er ¹

Origin of buffer²

First recorded in 1850–55; buff ¹ + -er ¹

Origin of buffer³

First recorded in 1745–50; origin uncertain

Explanation

A buffer is an object that either softens a blow like a fender, or helps buff or shine stuff, like a nail buffer. Buffer comes from the Old French buff, a word that imitates the sound of a blow to a soft body. A person can also be a buffer if she keeps people prone to fighting from coming in contact or hurting each other, like a teacher who separates two rowdy kids at the lunch table. A buffer state is a country between two conflicting ones that helps them better get along by creating a buffer between them — like Mongolia is for China and Russia.

Example Sentences

With their 2-1 win on Monday night, they moved to 36 points to open a six-point buffer between them and the relegation zone with six matches left.

From BBC • Apr. 13, 2026

When U.S. interest rates move in one direction, the yield on emerging-market bonds tends to move in the other, helping to buffer volatility.

From The Wall Street Journal • Apr. 9, 2026

“That added cash flow is helping support larger purchases, including vehicles, and providing a partial buffer against higher prices at the pump,” Skordeles says.

From Barron's • Apr. 8, 2026

The fact that the so-called fundamentals appear to be holding up also has helped to serve as a buffer for markets.

From MarketWatch • Apr. 7, 2026

In the process, China would lose a key buffer between one of its poorest regions and a united, affluent, and West-oriented Korea.

From "Escape from Camp 14: One Man's Remarkable Odyssey from North Korea to Freedom in the West" by Blaine Harden

Related Words

• bulwark
• cushion
• intermediary