| Abbreviation | Definition |
|---|---|
| PEL | Precision Elastic Limit |
| PEM | Plant Engineering and Maintenance |
| PEN | Penicillin |
| PEP | Performance Evaluation Profile |
| PEP | Power Extension Package |
| PEP | Propellant Equilibrium Program |
| PEPE | Plasma Experiment For Planetary Exploration |
| PER | Perigee |
| PER | Period |
| PER | Preliminary Engineering Report |
| PER | Pyrotechnic Energy Release |
| PERD | Payload Element Requirements Document |
| PERF | Perform, Performance |
| PERN | Parellel Earth Resources Negligable |
| PERN | Preliminary Engineering Release Notice |
| PERT | Position Error Recovery Time |
| PERT | Program Evaluation Review Technique |
| PERTCO | Program Evaluation And Review Technique With Cost |
| PES | Post Ejection Sequencer |
| PET | Phase Elapsed Time |