| Abbreviation | Definition |
|---|---|
| ER | Evaluate Refute |
| ER | Everybody Run |
| ER | Evidence Rules (court rules) |
| ER | Expert Resources |
| ERA | Educational Rights Agenda |
| ERA | Elements, Rules, and Applications |
| ERD | Expected Release Date |
| ERISA | Employee Retirement Income Security Act |
| ERTB | European Retail Theft Barometer |
| ERTK | Employee Right-To-Know |
| ES | Elevated Standard |
| ES | Enhanced Security |
| ES | Evidence Symmetry |
| ESB | East Side Bloodz |
| ESC | Extreme Street Conversion |
| ESE | Ever So Evil |
| ESF | Elite Swat Forces |
| ESI | Electronically Stored Information |
| ESP | Eastern State Penitentiary |
| ESQ | Ecstatic Soul Quintet |