noun (1)
buff·​er | \ ˈbə-fər How to pronounce buffer (audio) \

Definition of buffer

 (Entry 1 of 4)

British slang
: fellow, man especially : an old man


noun (2), often attributive

Definition of buffer (Entry 2 of 4)

1 : any of various devices or pieces of material for reducing shock or damage due to contact
2 : a means or device used as a cushion against the shock of fluctuations in business or financial activity
3 : something that serves as a protective barrier: such as
b : a person who shields another especially from annoying routine matters
4 : a substance capable in solution of neutralizing both acids and bases and thereby maintaining the original acidity or basicity of the solution also : a solution containing such a substance
5 : a section of computer memory for temporarily storing information especially : one that accepts information at one rate and delivers it at another The streaming video feed continues to download into the buffer while the computer starts playing the movie.


buffered; buffering\ ˈbə-​f(ə-​)riŋ How to pronounce buffer (audio) \

Definition of buffer (Entry 3 of 4)

transitive verb

1 : to lessen the shock of : cushion
2 : to treat (something, such as an acid solution) with a buffer also : to prepare (aspirin) with an antacid
3 : to collect (data) in a buffer


noun (3)

Definition of buffer (Entry 4 of 4)

: one that buffs

Other Words from buffer

Noun (2)

buffered \ ˈbə-​fərd How to pronounce buffer (audio) \ adjective

Examples of buffer in a Sentence

Verb The trees help buffer the house from the hot summer sun. The wall buffers the noise of the traffic.

First Known Use of buffer

Noun (1)

1749, in the meaning defined above

Noun (2)

1835, in the meaning defined at sense 1


1845, in the meaning defined at sense 1

Noun (3)

1854, in the meaning defined above

History and Etymology for buffer

Noun (1)

origin unknown

Noun (2)

buff, verb, to react like a soft body when struck

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Dictionary Entries Near buffer



buffer state

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Cite this Entry

“Buffer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/buffer. Accessed 22 May. 2022.

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More Definitions for buffer


buff·​er | \ ˈbəf-ər How to pronounce buffer (audio) \

Medical Definition of buffer

 (Entry 1 of 2)

1 : a substance or mixture of substances (as bicarbonates and some proteins in biological fluids) that in solution tends to stabilize the hydrogen-ion concentration by neutralizing within limits both acids and bases


transitive verb

Medical Definition of buffer (Entry 2 of 2)

: to treat (as a solution or its acidity) with a buffer also : to prepare (aspirin) with an antacid

More from Merriam-Webster on buffer

Nglish: Translation of buffer for Spanish Speakers

Britannica English: Translation of buffer for Arabic Speakers

Britannica.com: Encyclopedia article about buffer


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