| Abbreviation | Definition |
|---|---|
| SHT | Short Histidine Tag |
| SHT | Systemic HyperTension |
| SI | SacroIliac |
| SI | Self Inflicted |
| SI | Self Injury |
| SI | Self Inserted |
| SI | Small Intestine |
| SI | Speech Impaired |
| SIA | Spectrophotometric Intracutaneous Analysis |
| SIADH | Syndrome Of Inappropriate Antidiuretic Hormone Secretion |
| SIAM | Self Injury Awareness Movement |
| SIAM | Sids Initial Assessment Meeting |
| SIB | Self Injurious Behavior |
| SIB | Severely Injured Brain |
| SICA | Schizont Infected Cell Agglutination |
| SICS | Spinal Immobilization Confinement System |
| SID | Once per day |
| SIDA | Síndrome de InmunoDeficiencia Adquirida |
| SIDS | Screening Information Data Set |
| SIDS | Sudden infant death syndrome |