buff·er

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun One that buffs, especially a piece of soft leather or cloth used to shine or polish.
• noun A buffing wheel.
• noun Something that lessens or absorbs the shock of an impact.
• noun One that protects by intercepting or moderating adverse pressures or influences.
• noun Something that separates potentially antagonistic entities, as an area between two rival powers that serves to lessen the danger of conflict.
• noun 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.
• noun Computers A device or area used to store data temporarily.
• transitive verb To act as a buffer for or between.
• transitive verb Chemistry To treat (a solution) with a buffer.
• transitive verb Computers To hold or collect (data) in a buffer.