Buff"er (bŭf"&etilde;r), n. [Prop a striker. See Buffet a blow.] 1. (Mech.) (a) An elastic apparatus or fender, for deadening the jar caused by the collision of bodies; as, a buffer at the end of a railroad car. (b) A pad or cushion forming the end of a fender, which receives the blow; -- sometimes called buffing apparatus.

2. One who polishes with a buff.

3. A wheel for buffing; a buff.

4. A good-humored, slow-witted fellow; -- usually said of an elderly man. [Colloq.] Dickens.

• Someone or something that buffs.
  
• (chemistry) A solution used to stabilize the pH (acidity) of a liquid.
  
• (computing) A portion of memory set aside to store data, often before it is sent to an external device or as it is received from an external device.
  
• (mechanical) Anything used to maintain slack or isolate different objects.
  
• (telecommunications) A routine or storage medium used to compensate for a difference in rate of flow of data, or time of occurrence of events, when transferring data from one device to another.
  
• An isolating circuit, often an amplifier, used to minimize the influence of a driven circuit on the driving circuit.
  
• In international relations, a buffer zone (such as a demilitarized zone) or a buffer state.
  
• To use a buffer or buffers; to isolate or minimize the effects of one thing on another.
  
• (computing) To store data in memory temporarily.