The first term implies the engine was checked for compression, had seals and timing replaced and is ready to run.
The other terms imply the engine was disassembled, cleaned, machined, and reassembled with either the same parts reconditioned ( rebuilt ) or all new parts ( remanufactured)
There are no standards so the terms are open to interpretation.
------ Follow up post added October 7th, 2011 06:28 PM ------
At 160k that engine is just reaching puberty.
1966 109 5 door wagon 300Tdi "spermaceti fueled"
1994 RRC LeWiB "ruining the air behind me"
All my troubles are Rover