| Acronym | Definition |
|---|
| SEP | September |
| SEP | Separate |
| SEP | Spherical Error Probable |
| SEP | State Energy Program |
| SEP | Simplified Employee Pension (IRS; type of IRA) |
| SEP | Saturday Evening Post (US Periodical) |
| SEP | Secretaria de Educacion Publica |
| SEP | Stanford Encyclopedia of Philosophy |
| SEP | Socialist Equality Party |
| SEP | Socialist Equality Party (Australia) |
| SEP | Separator (orthodontics; programming) |
| SEP | Someone Else's Problem |
| SEP | Secretaría de Educación Pública (Spanish) |
| SEP | Search Engine Promotion |
| SEP | Search Engine Positioning |
| SEP | Summer Enrichment Program |
| SEP | Sclerose en Plaque (French: Multiple Sclerosis) |
| SEP | Student Exchange Program |
| SEP | South End Press |
| SEP | Somebody Else's Problem (Douglas Adams, Hitchhiker's Triology) |
| SEP | Somatosensory Evoked Potential |
| SEP | Supplemental Environmental Projects (US EPA) |
| SEP | Single Entry Point |
| SEP | Special Emphasis Panel |
| SEP | Systems Engineering Plan |
| SEP | Special Emphasis Program |
| SEP | Société en Participation (French: Joint Venture; business structure) |
| SEP | Single Engine Piston (type rating for JAA Pilots License) |
| SEP | Systems Engineering Process |
| SEP | Sexual Encounter Profile |
| SEP | Senior Executive Program |
| SEP | Solar Energetic Particles |
| SEP | Sound Engineering Practice(s) |
| SEP | Syringe Exchange Program |
| SEP | Sequential Exchange Protocol (computer networking) |
| SEP | Solar Electric Propulsion |
| SEP | Special Election Period (US Medicare) |
| SEP | Science Education Programs |
| SEP | Scottish Equity Partners |
| SEP | System Enhancement Program (US Army M1A2 tank) |
| SEP | Secure Electronic Payment |
| SEP | Secondary Education Program |
| SEP | Solvent Extraction Process |
| SEP | Soldier Enhancement Program |
| SEP | System Engineering Process |
| SEP | Science Enhancement Programme (UK) |
| SEP | Single Exit Price (South Africa) |
| SEP | Symmetric Eigenproblems |
| SEP | Science Enrichment Program (University of Massachusetts Amherst) |
| SEP | Secondary Education Project |
| SEP | Sociedade Brasileira de Economia Politica (Brasil) |
| SEP | Saturday Enrichment Program |
| SEP | Safety Enhancement Program |
| SEP | Stanford Executive Program |
| SEP | Signaling End Point |
| SEP | Sistema de Estudios de Posgrado (Costa Rica) |
| SEP | Serum Electrophoresis |
| SEP | Symbol Error Probability |
| SEP | Specific Excess Power |
| SEP | Surface Electrical Properties |
| SEP | Sociedad Española de Pedagogía (Spain) |
| SEP | Single Edge Processor |
| SEP | State Emergency Plan |
| SEP | Smallpox Eradication Program (WHO) |
| SEP | Society for Exact Philosophy |
| SEP | Strategische Erfolgspositionen (German: strategic success positions) |
| SEP | Service Entry Point (call center software) |
| SEP | Scalable Encryption Processing |
| SEP | Sociedad Española de Paleontologia (Spain) |
| SEP | Society of Experimental Psychologists |
| SEP | Service de l'Emploi Pénitentiaire (French: Prison Employment Service) |
| SEP | Summer Education Program |
| SEP | Sociedade Esportiva Palmeiras (Brazilian soccer club) |
| SEP | Storage Enclosure Processor |
| SEP | Staff Exchange Program |
| SEP | Supplemental Environmental Program |
| SEP | Site Emergency Plan |
| SEP | Simple Exclusion Process |
| SEP | Salmon Enhancement Program (est. 1977; Fisheries and Oceans Canada) |
| SEP | Special Embassy Program |
| SEP | Service Enhancement Program |
| SEP | Systems Enhancement Program |
| SEP | Supplementary Environmental Project (EPA) |
| SEP | Single-Event Phenomena (radiation and semiconductor electronics) |
| SEP | Standard Evaluation Procedures (EPA) |
| SEP | System Evaluation Plan |
| SEP | Signal Entry Panel |
| SEP | Service de l'Enseignement Prive (French: Service of Private Teaching, Geneva) |
| SEP | Security Evaluation Program |
| SEP | Secure Exchange Protocol |
| SEP | Secretariado de Estudios Propios |
| SEP | Syndicat de l'Education Populaire (French: Union of Popular Education) |
| SEP | Strathclyde European Partnership Ltd (UK) |
| SEP | Systematic Evaluation Program |
| SEP | Software Enhancement Proposal |
| SEP | Swine Enzootic Pneumonia (mycoplasmosis) |
| SEP | Scorched Earth Productions |
| SEP | Sanctuary Education Panel (NOAA) |
| SEP | Software Entwicklungs Praktikum |
| SEP | Severely Errored Period |
| SEP | Secretaría Ejecutiva de la Presidencia (Spanish) |
| SEP | Selsius Ethernet Phone |
| SEP | Société d'Equipement du Poitou (French: Equipment Corporation of Poitou) |
| SEP | Special Energy Programme (Kenya) |
| SEP | Swiss Expert Pool (for Civilian Peacebuilding) |
| SEP | Standard Error Prediction |
| SEP | Satellite Education Program |
| SEP | Safety and Emergency Procedure |
| SEP | sealift enhancement program (US DoD) |
| SEP | Société d'Encouragement au Progrès |
| SEP | Sequence Endpoint |
| SEP | Science Entrepreneurship Program (Case Western Reserve University) |
| SEP | Software End Product |
| SEP | Safety Evaluation Panel |
| SEP | Service Engineering Process |
| SEP | Safety Evaluation for Packaging |
| SEP | Selective Employment Plan |
| SEP | Spherical Error of Probability |
| SEP | Synthetic Environment Program |
| SEP | Strain Energy Partitioning |
| SEP | System Enhancement Proposal |
| SEP | Simultaneous Examination Program (US IRS) |
| SEP | Spanning Explorer Packet (Cisco) |
| SEP | signal entrance panel (US DoD) |
| SEP | Service Execution Plan |
| SEP | Solar Electron Package |
| SEP | Software Execution Platform |
| SEP | Somebody's Elses Problem |
| SEP | Site Evaluation Panel |
| SEP | Solar Energetics Package |
| SEP | Support/Standard Equipment Plan |
| SEP | Stable Element Panel |
| SEP | Shipbuilders' Estimating Package |
| SEP | Scientific & Engineering Personnel |
| SEP | Selectively Enhanced Polymer |
| SEP | Strategic Execution Planning |
| SEP | SOSUS Estimated Position |
| SEP | Schema-Evolution Pattern |
| SEP | Screaming Eagle Poker |
| SEP | Supportive Employment Program (various organizations) |
| SEP | Science and Engineering Program (Boston University) |
| SEP | Southeast Europe Project (Woodrow Wilson Center) |
| SEP | Self Employed Person (classification) |
| SEP | Software Engineering Process |
| SEP | Superior Energy Performance (certification program) |
| SEP | Special Enrollment Period (Medicare) |
| SEP | Screamin' Eagle Performance (motorcycle parts) |
| SEP | Symantec Endpoint Protection |
| SEP | Sygate Enterprise Protection (Symantec) |
| SEP | Senior Employment Program (various locations) |
| SEP | Special Education Program (various organizations) |
| SEP | Solvay Engineered Polymers (various locations) |
| SEP | Science Education Partnership (various locations) |
| SEP | Self-Employed Professional |