Radiation Experiment
Reactive EXtrusion
Reflector Erosion Experiment
Relativistic Electronbeam Experiment
Relocatable Executable
Remote Events for XML
Routine Exercise
Radiation Exposure System
Radiological Exposure System
Ram Air Freight
Real Enviroment Extreme
Real-Time Executive
Receiver Exciter
Regional Energetics Experiment
Regional Express
regulator x
Remote EXecution
Remote Execution Facility
Remote Execution Service
Request to Exit Device
Requisition Exception Code
Residence EXploration and selection
resistance exercise
Robotic Excavator
Route Extension