[ buhf-er ]
See synonyms for buffer on Thesaurus.com
  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.

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

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

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

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

  5. 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.

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

  7. Chemistry.

    • 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.

    • Also called buff·er so·lu·tion [buhf-er suh-loo-shuhn] /ˈbʌf ər səˌlu ʃən/ . a solution containing such a substance.

verb (used with object)
  1. Chemistry. to treat with a buffer.

  2. to cushion, shield, or protect.

  1. to lessen the adverse effect of; ease: The drug buffered his pain.

  2. Digital Technology. to temporarily save (data) before actively accessing it so that it can be loaded at a rapid or uniform rate: 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.

Origin of buffer

First recorded in 1825–35; buff2 + -er1

Other words from buffer

  • un·buff·ered, adjective

Words Nearby buffer

Other definitions for buffer (2 of 3)

[ buhf-er ]

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

  2. a worker who uses such a device.

Origin of buffer

First recorded in 1850–55; buff1 + -er1

Other definitions for buffer (3 of 3)

[ buhf-er ]

nounBritish Slang.
  1. a foolish or incompetent person.

  2. a fellow; man.

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

Origin of buffer

First recorded in 1745–50; origin uncertain

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2024

How to use buffer in a sentence

British Dictionary definitions for buffer (1 of 3)


/ (ˈbʌfə) /

  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

  1. chem

    • 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

    • Also called: buffer solution a solution containing such a compound

  2. computing a memory device for temporarily storing data

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

  4. short for buffer state

  5. hit the buffers informal to finish or be stopped, esp unexpectedly

  1. to insulate against or protect from shock; cushion

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

Origin of buffer

C19: from buff ²

British Dictionary definitions for buffer (2 of 3)


/ (ˈbʌfə) /

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

  2. a person who uses such a device

British Dictionary definitions for buffer (3 of 3)


/ (ˈbʌfə) /

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

Origin of buffer

C18: perhaps from Middle English buffer stammerer

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for buffer


[ bŭfər ]

  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.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

Cultural definitions for buffer


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

Notes for buffer

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

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.