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buff·er 1 (bŭfər)
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n.
1. One that buffs, especially a piece of soft leather or cloth used to shine or polish.
2. A buffing wheel.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 
buff·er 2 (bŭfər)
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n.
1. Something that lessens or absorbs the shock of an impact.
2. One that protects by intercepting or moderating adverse pressures or influences: "A sense of humor ... may have served as a buffer against the ... shocks of disappointment" (James Russell Lowell).
3. Something that separates potentially antagonistic entities, as an area between two rival powers that serves to lessen the danger of conflict.
4. Chemistry A solution that resists a change in acidity when an acid or base is added to it, or a substance that facilitates this resistance.
5. Computers A device or area used to store data temporarily.
tr.v. buff·ered, buff·er·ing, buff·ers
1. To act as a buffer for or between.
2. Chemistry To treat (a solution) with a buffer.
3. Computers To hold or collect (data) in a buffer.

[Probably from obsolete buff, to make a sound like a soft body being hit, of imitative origin.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2022 by HarperCollins Publishers. All rights reserved.
 

Indo-European & Semitic Roots Appendices

    Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

    Indo-European Roots

    Semitic Roots

    The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.