FSOS
| Acronym | Definition |
|---|---|
| FSOS | Free-Space Optical System |
| FSOS | Friendly Sons of the Shillelagh (New Jersey) |
| FSOS | Fifty Shades of Sexy |
| FSOS | Food Service Operating Supplies |
| FSOS | Family Support Orders Service (Canada) |
| FSOS | Future Sounds of Swing |
| FSOS | For the Sake of the Salmon (est. 1995) |
| FSOS | False Sense of Security (Exies song title) |
| FSOS | Functional Significance of Stereopsis (medicine) |
| FSOS | Free Standing Operating System |
| FSOS | Flight Support Operations and Services |