| Acronym | Meaning |
| SST | SuperSonic Transport -Training Submarine (US Navy Hull Classification) - Saturated Suction Temperature (refrigeration Cycles) |
| SOS | Somali Shilling (ISO 4217 Currency Code) |
| POSSLQ | Person Of The Opposite Sex Sharing Living Quarters |
| BE | Beryllium |
| PW | Palau (postal Symbol; ISO 3166 Digram) - Petawatt |
| PYF | French Polynesia (ISO 3166 Trigram) |
| FLK | Falkland Islands (ISO 3166 Trigram) -Funny-Looking Kid (medical Diagnosis In-joke) |
| JO | Jordan (FIPS 10-4 Country Code; ISO 3166 Digram) |
| GEC | Great Engineering Challenge |
| ESE | East South-East |