buff·er 2 
(bŭfər)
(bŭfər)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.]