jiffy

jiffy n.  1. The duration of one tick of the system clock on
   the computer (see {tick}).  Often one AC cycle time (1/60 second
   in the U.S. and Canada, 1/50 most other places), but more recently
   1/100 sec has become common.  "The swapper runs every 6 jiffies"
   means that the virtual memory management routine is executed once
   for every 6 ticks of the clock, or about ten times a second.
   2. Confusingly, the term is sometimes also used for a 1-millisecond
   {wall time} interval.  Even more confusingly, physicists
   semi-jokingly use `jiffy' to mean the time required for light to
   travel one foot in a vacuum, which turns out to be close to one
   *nanosecond*.  3. Indeterminate time from a few seconds to
   forever.  "I'll do it in a jiffy" means certainly not now and
   possibly never.  This is a bit contrary to the more widespread use
   of the word.  Oppose {nano}. See also {Real Soon Now}.