jiffy

noun5

1. •
   (informal) A very short, unspecified length of time.

   • I’ll be back in a jiffy.
2. •
   (UK) Ellipsis of jiffy bag, a padded envelope.
3. •
   A unit of time defined by the frequency of its basic timer – historically, and by convention, 0.01 of a second, but some computer operating systems use other values.

   • The number of processed packets per round is limited in dependence of the page size. The processed packets are forwarded to a single queue and are processed for the time of two jiffies. — 2015
4. •
   The length of an alternating current power cycle (1/60 or 1/50 of a second).
5. •
   The time taken for light to travel a specified distance in a vacuum, usually one centimetre (approximately 33.3564 picoseconds), but sometimes one foot or the width of a nucleon.