| Acronym | Meaning |
| PPM | Parts Per Million |
| LZ | Bulgaria (amateur Radio ITU Prefix) -Landing Zone |
| IMPACT | International Medical Products Anti-Counterfeiting Taskforce |
| TTD | Trinidad And Tobago Dollar (ISO 4217 Currency Code) |
| RM | Raeto-Romansh Language (ISO 639-1 Code) |
| O | Oberst - Observer - Obstacle - Octal - Officer - Official - Oh - Operational - Operator - Oprah (magazine) - Outstanding -Oxygen |
| EMU | Electric Multiple Unit - A Method Of Connecting Self-propelled Railway Vehicles Together To Form A Train Under The Control Of One Driver. |
| ZK | Zeptokelvin |
| USCINCSPACE | United States Commander In Chief |
| IVO | In Vicinity Of |