sophomore synthesis soporific synthetic sore syphilis sour syringe souvenir syrup Soviet systole sow soybean spacious spade span spark sparkle sparrow sparse spasm spear specialize specialty species specific specification specify specimen speck spectacle spectacular spectator spectrum speculate speculation sperm sphere spherical sphincter sabotage sphygmomanometer sac spice sack spider sacred spill sacrifice spin sadden spinal saddle spindle saint spiral sake spire saline spiritual salubrious spit salutary spite salute splash salvage splay salve spleen sanatorium splint sane split sanitarian spoil sanitary sponge sarcasm spongy sardine sponsor satchel spontaneous satellite spoon satire spoor saturate spore saturation spot sauce spotted saucer spouse sausage sprain savage sprawl saw spray scab sprinkle scabies sprout scale spurt scalp sputum scalpel squad scan squalors scanty squeeze scar squint scarce squirrel scare stab scarf stable scarlet stack scatter stadium scavenge stagger scene stagnant scenery stain scent stainless schistosomiasis staircase schizophrenia stake sclerosis stale scorch stall scorn stammer scout starch scramble startle scrape starvation scratch starve screen static screw stationary screwdriver stationery script statistical scrub statistics scrupulous statue scrutinize stature scurvy status seagull steamer seal steep secrecy steer secretary stem secrete steppe secretive stereo section stereotype security sterile sedative sterilization sedentary sterilize sediment sternum seep steroid segment stethoscope segregation steward seize stick selfish stiff semester stiffness semiconductor stifle seminar stimulant senate stimulate senesce stimulation senescent stimulus senile sting senior stipulate sensation stir sensational stitch sensitivity stock sensitize stocking sensory stool sentiment stoop separator storage septic storey sequel stout sequence stove serial strain serology strap serpent strategic serum strategy sesame straw session strawberry sever stray severe streak sewage streamline shabby strenuous shady streptomycin shame stretch shameful stricture shampoo stride shareholder string shave strip shear stripe sheath strive shed stroke sheer stroll shell strut shelter stubborn shield stud shift studio shilling stuff shipwreck stumble shiver stun shovel stupor shower sturdy shrewd subconscious shriek subcutaneous shrill subdivide shrimp subdue shrink subjective shrinkage subjunctive shrug sublethal shudder submarine shunt submerge shuttle submit sickle subordinate sieve subscribe sift subscription sigh subsequent sigmoid subside signage subsidiary signature subsidy silicon substitute silicosis substitution simplicity substrate sin subtle sincere subtract singularity suburb sinus suburban sip succumb site suck situate sue skeleton suffice sketch suffocate skid suicide skull suite slack sulfa slander sulphate slang sulphur slap summarize slaughter summary sleeve summit slender summon slice sumptuous slide sunburnt slim superb slip superficial slipper superfluous slippery superior slit supersonic slogan superstition slope supervene slot supervise slough supervision sluggish supine slum supposition slumber suppress sly suppuration smallpox supreme smash surpass smear surplus smother surprise smuggle surrender snack surveillance snag survey snail susceptible snap suspect snatch suspend sneer suspicion sneeze suspicious sniff sustain snob sustainable snore suture snuff swab soak swamp soap swarm soar sway sob swear sober swell sociological swerve sociologist swift sociology swing socket switch sodium sword sole syllabus solemn symbol solicit symbolic solidarity symmetrical solidify symmetry solitary sympathetic solitude sympathize soluble sympathy solute symphony solution symposium solvent symptom somatic syncope soothe syndrome sophisticated synonym