| SDU | standard deviation unit; step-down unit |
|---|---|
| DS | dead air space; dead space; deep sedative; deep sleep; defined substrate; dehydroepiandrosterone sul... |
| STEP | Sequential Test of Educational Programs |
| ECG | Electro-Cardio-Graphy(-Gram); 심전도 = EKG 1. Conducting System Structu... |
| ST | esotropia; scala tympani; scaphotrapezoid; sclerotherapy; sedimentation time; semitendinosus; sensor... |