[1] : The Collaborative International Dictionary of English v.0.48

reentrant \reen"trant\ -trant, a.
   reentering; pointing or directed inwards; as, a reentrant
   angle.
   1913 webster

[2] : WordNet (r) 2.0

re-entrant
     adj : of angles pointing inward; "a polygon with re-entrant
           angles" syn: reentrant ant: salient
see also:
reentrant salient 

[3] : WordNet (r) 2.0

reentrant
     adj : of angles pointing inward; "a polygon with re-entrant
           angles" syn: re-entrant ant: salient
see also:
re-entrant salient 

[4] : The Free On-line Dictionary of Computing (27 SEP 03)

re-entrant
     
         used to describe code which can have multiple
        simultaneous, interleaved, or nested invocations which will
        not interfere with each other.  this is important for
        parallel processing, recursive functions or subroutines,
        and interrupt handling.
     
        it is usually easy to arrange for multiple invocations
        e.g. calls to a subroutine to share one copy of the code and
        any read-only data but, for the code to be re-entrant, each
        invocation must use its own copy of any modifiable data or
        synchronised access to shared data.  this is most often
        achieved using a stack and allocating local variables in a
        new stack frame for each invocation.  alternatively, the
        caller may pass in a pointer to a block of memory which that
        invocation can use usually for outputting the result or the
        code may allocate some memory on a heap, especially if the
        data must survive after the routine returns.
     
        re-entrant code is often found in system software, such as
        operating systems and teleprocessing monitors.  it is also
        a crucial component of multithreaded programs where the term
        "thread-safe" is often used instead of "re-entrant".
     
        1996-12-21
     
     
see also:
parallel processing recursive interrupt handling stack stack frame heap 
operating systems teleprocessing monitors multithreaded 

Re-Entrant >> R Words
Re-Entrant, definition of term: Re-Entrant
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