In the aircraft world the words "rebuilt" or "remanufactured" can only be
used of parts or engines that have been done by either the original
manufacturer or a repair station that is approved by the original
manufacturer.  When you get a rebuilt engine from one of these sources it is
"zero timed" basically a new engine as far as time goes.  Now I could
"rebuild" an engine, use all new parts internally and have the case tested,
etc, and basically do the same or even a better job as the manufacturer, but
since I don't have an approval from them my best efforts would only be called
"overhauled" and would not be "zero timed".  Welcome to the wonderful world
of nomenclature!
As an AC mech you have to be part lawyer :)
Just FYI.
Ken Wilford
Van-Again
John 3:16