fossil

   1.  In  software,  a  misfeature  that becomes understandable only in
   historical  context, as a remnant of times past retained so as not to
   break  compatibility. Example: the retention of octal as default base
   for  string  escapes  in  {C},  in  spite  of  the  better  match  of
   hexadecimal  to  ASCII and modern byte-addressable architectures. See
   {dusty deck}.

   2.  More  restrictively,  a feature with past but no present utility.
   Example: the force-all-caps (LCASE) bits in the V7 and {BSD} Unix tty
   driver, designed for use with monocase terminals. (In a perversion of
   the   usual   backward-compatibility  goal,  this  functionality  has
   actually been expanded and renamed in some later USG Unix releases as
   the IUCLC and OLCUC bits.)

[glossary]
[Reference(s) to this entry by made by: {bug-compatible}{dusty deck}{QWERTY}]