dangling pointer

dangling pointer
 n.

   [common] A reference that doesn't actually lead anywhere (in C and
   some other languages, a pointer that doesn't actually point at
   anything valid). Usually this happens because it formerly pointed to
   something that has moved or disappeared. Used as jargon in a
   generalization of its techspeak meaning; for example, a local phone
   number for a person who has since moved to the other coast is a
   dangling pointer.
    

dangling pointer

   <programming> A reference that doesn't actually lead anywhere.
   In {C} and some other languages, a pointer that doesn't
   actually point at anything valid.  Usually this happens
   because it formerly pointed to something that has moved or
   disappeared, e.g. a {heap}-allocated block which has been freed
   and reused.

   Used as jargon in a generalisation of its technical meaning;
   for example, a local phone number for a person who has since
   moved is a dangling pointer.

   [{Jargon File}]