| Term | Definition |
| Rout | to force out |
| Rove | roam |
| Rueful | sorrowful |
| Ruminate | to meditate upon; to muse at length; to chew over; to ponder |
| Saffron | orange or yellow |
| Sagacious | wise, esp. from experience |
| Salient | standing out conspicuously; of immediate importance; prominent; striking |
| Saline | salty |
| Sanctimonious | pretending to be virtuous or devout; pretending to be righteous |
| Sanguine | red like blood; hopeful, anticipating the best |
| Sapient | wise, sagacious |
| Sardonic | bitterly scornful, sarcasatic |
| Saturnine | gloomy; morose |
| Savant | a learned person |
| Savvy | shrewd, catching on quickly |
| Scintillate | to sparkle |
| Scion | offspring |
| Scrupulous | conscientious and careful to detail – having ethical values |
| Scurrilous | using language containing indecency or abuse; obscenely joking; vulgar |
| Sebaceous | oily, greasy |
| Secular | relating to wordly things, not religious |
| Sedate | to calm or to sooth |
| Sedentary | characterized by sitting; not moving |
| Sedition | rebellion; conduct that is rebellious |
| Segue | an immediate transition from one thing to another |
| Semblance | an outward appearance |
| Sensate | perceived through the senses |
| Shard | a fragment or piece |
| Shrewd | astute, keen, cunning |
| Simile | a comparison using like or as |
| Sinecure | any office or position that brings profit without work or responsibility |
| Sinister | evil, threatening |
| Sinuous | bending in and out; winding; serpentine |
| Slothful | lazy |
| Sobriquet | a nickname |
| Somniferous | inducing sleep |
| Somnolent | inclined or heavy with sleep; drowsy; sleepy; of a kind likely to induce sleep |
| Sonorous | producing, full or loud sound; imposing or impressive in effect or style |
| Sophistry | clever but deceptive reasoning; plausible but misleading argument |
| Soporific | sleep inducing |
| Spate | a flood of something |
| Spawn | to lay eggs; to engender or create; to give birth to; to produce |
| Sporadic | happening only occasionally |
| Sprite | an elf-like spirit |
| Spurious | false or untrue |
| Staid | primly self-restrained; serious-minded |
| Stationary | not moving |
| Stentorian | extremely loud |
| Stolid | showing little emotion |
| Stringent | strict, rigid |
| Stripling | a young lad |
| Stygian | gloomy and dark; hellish; infernal (like the River Styx in the mythical Underworld) |
| Stymie | to obstruct or impede |
| Subservient | obsequious; servile, excessively submissive |
| Subside | to lessen, abate, wane, ebb |
| Substantiate | to verify, prove true |
| Subterfuge | a deception; artifice; a trick or tactic used to avoid or conceal something |
| Subtle | faint, lightly suggestive |
| Succinct | brief, concise |
| Succumb | to yeild; give away to a superior force |
| Suffuse | to overspread; to spread through; saturate |
| Sultry | hot and moist; seductively "hot" |
| Superfluity | an excessive amount of something—luxury or insincerity |
| Suppleness | flexibility, ability to bend easily |
| Surfeit | a glut, excess |
| Surly | hostile, sullenly rude |
| Surreptitious | done by stealth or without proper authority |
| Swarthy | dark-colored; tanned by the sun |
| Swathe | to wrap or bind |
| Sycophant | a self-seeking, servile flatterer; one who attempts to win favor by flattering persons of influence |
| Synchronized | occuring at the same time |
| Synecdoche | using a part to represent the whole |
| Synopsis | a plot summary |
| Synthesis | a combination |
| Tarry | to linger; loiter |
| Teetotaler | one who refrains from alcohol |
| Tempestuous | stormy,tumultuous |
| Tenebrous | dark, gloomy |