| Abbreviation | Definition |
|---|---|
| SIRI | Sandy Is Realy Intelligent |
| SISB | School Is So Boring |
| SISI | School Is So Irritating |
| SISO | Slow Input, Slow Output |
| SISTER | Sassy, Intelligent, Smart, Talented, Elegant, Raunchy |
| SISTER | Supportive, Intelligent, Sweet, Talented , Encouraging, Reliable |
| SITB | Sippin In The Basement |
| SITH | Smeg In The Head |
| SITNC | Smart Is The New Cool |
| SJN | Single Jewish Nutcase |
| SJR | Sam And John Relationship |
| SK | Stop Knudsen |
| SK | Swat Kats |
| SK9 | Simply Kanine |
| SKB | Smoochy Kitty Baby |
| SKF | Spindly Killa Fish |
| SKFL | Street Kid For Life |
| SKGD | Singing Kangaroos Go Downstairs |
| SKIN | Spend Kids Inheritance Now |
| SKIN | Spending Kids Inheritance Now |