| Abbreviation | Meaning |
|---|---|
| s̅ | without (s with an overbar) (from Latin sine) |
| S | sacrum |
| Sx | symptoms surgery (though deemed by some as inappropriate) |
| S1 | first heart sound |
| S2 | second heart sound |
| S3 | third heart sound |
| S4 | fourth heart sound |
| S&O | salpingo-oophorectomy |
| Sb | Scholar batch |
| SAAG | serum–ascites albumin gradient |
| SAB | staphylococcal bacteremia spontaneous abortion (that is, miscarriage) |
| SAD | seasonal affective disorder subacromial decompression |
| SAH | subarachnoid hemorrhage |
| SAM | systolic anterior motion of the mitral valve Severe acute malnutrition |
| SAN | sinoatrial node |
| SaO2 | arterial oxygen saturation |
| SAPS II | simplified acute physiology score |
| SAPS III | simplified acute physiology score |
| SAR | seasonal allergic rhinitis sub-acute rehabilitation facility |
| Sarc | sarcoidosis |
| SARS | severe acute respiratory syndrome |
| SB | small bowel (see small intestine) |
| SBE | subacute bacterial endocarditis |
| SBFT | small bowel follow through |
| SBMA | spinal and bulbar muscular atrophy |
| SBO | small bowel obstruction |
| SBP | systolic blood pressure spontaneous bacterial peritonitis |
| SBR | Serum Bilirubin |
| SBRT | split beam radiation therapy |
| SC | Spinal Cord or subcutaneous (from Latin subcutis ) |
| SCA | spinocerebellar ataxia |
| SCAT | sex cord tumor with annular tubes |
| SCC | squamous cell carcinoma |
| SCD | sequential compression device sickle-cell disease sudden cardiac death |
| SCI | spinal cord injury |
| SCID | severe combined immunodeficiency |
| SCIWORA | spinal cord injury without radiographic abnormality |
| SCLC | small cell lung cancer |
| scope | microscope or endoscope |
| SCT | sacrococcygeal tumor |
| SCZ | schizophrenia |
| S.D. | subdermal |
| SD σ | standard deviation |
| SDH | subdural hematoma |
| SDTI | suspected deep tissue injury |
| SE | standard error side effect |
| Sed | sedimentation (rate) (see erythrocyte sedimentation rate) |
| SEE | syphilis elimination effort |
| Segs | segmented cells |
| SEM | standard error of the mean systolic ejection murmur (see heart murmur) |
| SERM | selective estrogen receptor modulator |
| SERT | serotonin transporter |
| SFA | superficial femoral artery serum folic acid |
| SGA | small for gestational age |
| SG cath | Swan–Ganz catheter (see pulmonary artery catheter) |
| SG | specific gravity (in urinanalysis) |
| SGB | stellate ganglion block |
| SGOT | serum glutamic oxaloacetic transaminase |
| SGPT | serum glutamic pyruvic transaminase |
| SH SHx | social history (personal habits, living situation, job) |
| SHBG | sex hormone-binding globulin |
| shob | shortness of breath (see dyspnea) |
| SHPT | secondary hyperparathyroidism |
| SHx | surgical history |
| SI | International System of Units suicidal ideation seriously ill sacroiliac (joint) |
| STAC | Scaffolding theory of cognitive aging |
| SIADH | syndrome of inappropriate antidiuretic hormone |
| SICU | surgical intensive care unit |
| SIBO | small intestinal bacterial overgrowth |
| SID | semel in die meaning once daily. Used only in veterinary medicine. |
| SIDS | sudden infant death syndrome |
| SIL | squamous intraepithelial lesion |
| SIMV | synchronized intermittent mechanical ventilation |
| si op. sit | if needed (from Latin si opus sit) |
| SIRS | systemic inflammatory response syndrome |
| SIT | stress inoculation training (see posttraumatic stress disorder) |
| SJS | Stevens–Johnson syndrome |
| SK | streptokinase |
| sl | sublingual |
| SLE | systemic lupus erythematosus |
| SLEV | St Louis virus |
| SLL | small lymphocytic lymphoma |
| SLN | sublingual nitroglycerin |
| SLN SLNB | sentinel lymph node biopsy |
| SLP | speech-language pathologist |
| SLR | straight leg raise (see Lasègue's sign) |
| SM | multiple sclerosis (from Latin sclerosis multiplex) submucosal Skeletal Muscle |
| SMA | sequential multiple analysis superior mesenteric artery spinal muscle atrophy |
| SMA-6 | six-channel serum multiple analysis |
| SMA-7 | serum metabolic assay |
| SMN | statement of medical necessity |
| SMS | senior medical student |
| SMT | spinal manipulative therapy |
| SMV | superior mesenteric vein |
| SN | student nurse skilled nursing |
| SNB | sentinel node biopsy (ductal carcinoma) |
| SNF | skilled nursing facility |
| SNHL | sensorineural hearing loss |
| SNP | sodium nitroprusside single nucleotide polymorphism |
| SNRI | serotonin–norepinephrine reuptake inhibitor |
| SNV | sin nombre virus (the most common type of hantavirus) single nucleotide variant |
| SO | salpingo-oophoritis |
| SOA | swelling of ankles |
| SOAP | subjective, objective, assessment, plan (how physicians’ notes may be organized) |
| SOB | shortness of breath (see dyspnea) |
| SOBOE | shortness of breath on exertion |
| SOL | space-occupying lesion |
| Sol | solution |
| SOOB | send out of bed sitting out of bed |
| SOP | sterile ophthalmic preparation |
| SORA | stable on room air |
| SOS | if needed (from Latin si opus sit) |
| SP s/p | status post; condition after" |
| SPE | streptococcal pyrogenic exotoxin |
| Spec | specimen |
| SPECT | single-photon emission computed tomography |
| SPEP | serum protein electrophoresis |
| SPET | single-photon emission tomography |
| spp. | species, as in bacterial species (e.g. Enterobacteriaceae spp.) |
| Sp. fl. | spinal fluid (see cerebrospinal fluid) |
| Sp. gr. | specific gravity |
| SPS | single point (walking) stick |
| SQ sq | subcutaneous |
| SR | slow release (see also time release technology (medicine)) Sinus rhythm |
| SpO2 | peripheral capillary oxygen saturation |
| SROM | spontaneous rupture of membranes |
| SRS | stereotactic radiotherapy sex reassignment surgery |
| SRU | shock resuscitation unit |
| ss ss | one-half (ss either with or without a bar over them) (from Latin semis) |
| SS | hemoglobin SS (HbSS) (see in sickle-cell disease = SS disease) subserosal Sjogren's Syndrome |
| S/S S/Sx | signs and symptoms |
| SSC | secondary sex characteristics |
| SSE | sterile speculum exam |
| SSEP | somatosensory evoked potential |
| SSI | sliding scale insulin |
| SSKI | potassium iodide solution |
| SSPE | subacute sclerosing panencephalitis |
| ssRNA | single-stranded RNA |
| SSRI | selective serotonin reuptake inhibitor |
| SSSI | skin and skin structure infection (also referred to as acute bacterial skin and skin structure infection - ABSSSI) |
| SSSS | staphylococcal scalded skin syndrome |
| SSS | sick sinus syndrome |
| ST | sore throat speech therapy |
| Staph. | Staphylococcus |
| STD | sexually transmitted disease |
| stat | immediately (from Latin statim) |
| STEC | Shiga toxin–producing Escherichia coli (another name for enterohemorrhagic E. coli) |
| STEMI | ST elevation myocardial infarction |
| STH | somatotropic hormone |
| STI | sexually transmitted infection soft tissue injury |
| STN | Subthalamic nucleus soft tissue neck |
| STNR | Symmetrical tonic neck reflex |
| STOP | surgical termination of pregnancy (sometimes suction termination of pregnancy) |
| Strep. Strepto. | Streptococcus |
| STS | serological test for syphilis soft tissue sarcoma |
| Subq | subcutaneous |
| SUD | substance use disorder |
| SUI | stress urinary incontinence |
| Supp | suppository |
| SUV | standardized uptake value |
| Sux | Suxamethonium chloride (Succinylcholine) |
| SV | seminal vesicle stroke volume |
| SVC | superior vena cava |
| SVD | spontaneous vaginal delivery simple vertex delivery |
| SVE | sterile vaginal examination |
| SVG | Saphenous vein graft |
| SVI | systemic viral infection |
| SVN | small volume nebulizer |
| SVR | systemic vascular resistance |
| SVT | supraventricular tachycardia |
| SW | Sturge–Weber syndrome |
| Sx | symptoms |
| SXA | single-energy X-ray absorptiometer |
| SXR | skull x-ray |
| Sz | seizure |
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