| Term | Definition |
| spry | full of life; active |
| spume | foam |
| spurious | deceitful; counterfeit |
| spurn | to reject |
| squalid | filthy; dirty |
| staccato | made up of short, abrupt sounds |
| stagnant | not flowing; stale; sluggish |
| staid | sedate; settled |
| stalemate | a deadlock; a draw |
| stalwart | strong; sturdy |
| stamina | endurance; resistance to fatigue |
| stance | attitude; posture |
| stark | complete; harsh; severe |
| static | inactive; motionless |
| stationary | standing still; not moving |
| statute | law; rule |
| steadfast | firm in purpose; dependable; constant |
| stench | a foul smell |
| stentorian | very loud |
| stereotyped | not original; commonplace |