The Free On-line Dictionary of Computing (30 December 2018):

oblique stroke
/
slash

    "/".  Common names include: (forward) slash;
   stroke; ITU-T: slant; oblique stroke.  Rare: diagonal;
   solidus; over; slak; virgule; INTERCAL: slat.

   Commonly used as the division operator in programming, and
   to separate the components in Unix pathnames, and hence
   also in URLs.  Also used to delimit regular expressions in
   several languages.

   (1996-09-24)