attoparsec

from Jargon File (4.4.4, 14 Aug 2003)

attoparsec
 n.

   About an inch. atto- is the standard SI prefix for multiplication by
   10^-18. A parsec (parallax-second) is 3.26 light-years; an attoparsec
   is thus 3.26 x 10^-18 light years, or about 3.1 cm (thus, 1
   attoparsec/{microfortnight} equals about 1 inch/sec). This unit is
   reported to be in use (though probably not very seriously) among
   hackers in the U.K. See {micro-}.

from The Free On-line Dictionary of Computing (8 July 2008)

attoparsec

   <unit, humour> About 31 mm (one inch).  "atto-" is the
   standard {SI} {prefix} for multiplication by 10^-18.  A parsec
   (parallax-second) is 3.26 light-years; an attoparsec is thus
   3.26 * 10^-18 light years.  Thus, one attoparsec per
   {microfortnight} is about one inch per second.

   This unit is reported to be in use (though probably not very
   seriously) among hackers in the UK.

   [{Jargon File}]

   (1996-12-08)

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