| Term | Definition |
| sadistic | inclined to cruelty |
| saga | Scandinavian myth; any legend |
| sagacious | perceptive; shrewd; having insights |
| salient | prominent |
| saline | salty |
| sallow | yellowish; sickly in color |
| salubrious | healthful |
| salutary | tending to improve; beneficial; wholesome |
| salvage | rescue from loss |
| sanctimonious | displaying ostentatious or hypocritical devoutness |
| sanction | approve; ratify |
| sanctuary | refuge; shelter; shrine; holy place |
| sanguinary | bloody |
| sanguine | cheerful; hopeful |
| sap | diminish; undermine |
| sarcasm | scornful remark; stinging rebuke |
| sardonic | disdainful; sarcastic; cynical |
| sartorial | pertaining to tailors |
| sate | satisfy to the full; cloy |
| satellite | small body revolving around a larger one |
| satiate | satisfy fully |
| satire | form of literature in which irony, sarcasm, and ridicule are employed to attack vice and folly |
| satirical | mocking |
| saturate | soak thoroughly |
| saturnine | gloomy |
| satyr | half human; half bestial |
| saunter | stroll slowly |
| savant | scholar |
| savor | enjoy; have a distinctive flavor; small or quality |
| savory | tasty; pleasing, attractive or agreeable |
| scabbard | case for a sword blade; sheath |
| scad | great quantity |
| scaffold | temporary platform for workers; bracing framework; platform for execution |
| scale | climb up; ascend |
| scanty | meager; insufficient |
| scapegoat | someone who bears the blame for others |
| scavenge | hunt through discarded materials for usable items; search especially for food |
| scenario | plot outline; screenplay; opera libretto |
| schematic | relating to an outline or diagram; using a system of sumbols |
| schism | division; split |
| scintilla | shred; least bit |
| scintillate | sparkle; flash |
| scoff | mock; ridicule |
| scotch | stamp out; thwart; hinder |
| scourge | lash; whip; severe punishment |
| scruple | fret about; hesitate for ethical reasons |
| scrupulous | conscientious; extremely thorough |
| scrutinize | examine closely and critically |
| scuffle | struggle confusedly; move off in a confused hurry |
| scurrilous | obscene; indecent |
| scurry | move briskly |
| scurvy | despicable; contemptible |
| scuttle | sink |
| seamy | sordid; unwholesome |
| sear | char or burn; brand |
| seasoned | experienced |
| secession | withdrawal |
| seclusion | isolation; solitude |
| secrete | hide away or cache; produce and release a substance into an organism |
| sect | separate religious body; faction |
| secular | worldly; not pertaining to church matter; temporary |
| sedate | full of or marked by dignity and seriousness: composed; grave |
| sedentary | requiring sitting |
| sedition | resistance to authority; insubordination |
| sedulous | diligent |
| seedy | run-down; decrepit; disreputable |
| seemly | proper; appropriates |
| seep | ooze; trickle |
| seethe | be disturbed; boils |
| seine | net for catching fish |
| seismic | pertaining to earthquakes |
| semblance | outward appearance; guise |
| seminal | germinal; influencing future developments; related to seed or semen |
| seminary | school for training future ministers; secondary school, especially for young women |
| senility | old age; feeblemindedness of old age |
| sensitization | process of being more sensitive or acutely responsive to an external agent or substance |
| sensual | devoted to the pleasure of the senses; carnal; voluptuous |
| sensuous | pertaining to the physical senses; operating through the senses |
| sententious | terse; concise; aphoristic |
| sentient | capable of sensation; aware; sensitive |
| sentinel | A person or special body of persons assigned to provide protection or keep watch over, for example: guard, sentry; lookout |
| septic | putrid; producing putrefaction |
| sepulcher | tomb |