| FOSS | Fiber Optics Sonar System | 光纤声纳系统 |
| FOSS | Funds Only Settlement Service | 仅资金结算服务 |
| FOSS | Free / Open-Source Software | 自由/开源软件 |
| FOSS | Free and Open Source Software | 自由和开源软件 |
| FOSS | Follow-On System Stock | 后续系统库存 |
| FOSS | Federal Intelligence Security Service | 联邦情报安全局 |
| FOSS | Fiber-Optic Sensor System | 光纤传感器系统 |
| FOSS | Full Option Science System | 全期权科学系统 |
| FOSS | Faculty Online Support Service | 教师在线支持服务 |
| FOSS | Family Of System Study | 系统系列研究 |
| FOSS | Free Open Source Software | 免费开源软件 |
| FOSS | Friends Of Shaldon School | 沙尔顿学校的朋友 |
| FOSS | Forum of Small States (UN) | 小国论坛（联合国） |
| FOSS | Field Operational Support System | 外勤业务支持系统 |