| supercilium | n. | 1 | colored stripe on bird’s head running from beak to just above the eye | |
| supercilium | n. | 2 | eyebrow | obsolete |
| supererogate | v. | to do more than required; to make up for lack in one by excess merit in another | ||
| superficies | n. | outer surface | ||
| superincumbent | adj. | lying or resting upon; overhanging; from above (as of pressure) | ||
| superinfection | n. | infection occurring during or after an earlier infection, especially after the use of antibiotics | ||
| superlunary | adj. | celestial or heavenly as opposed to worldly | ||
| supermalagorgeous | adj. | terrific | slang | |
| supernal | adj. | of heaven; belonging to higher plane of existence | ||
| superpurgation | n. | excessive purgation, vomiting, or evacuation of the bowels | ||
| supervalent | adj. | of or related to the exaggerated importance given thoughts by a thinker which that thinker cannot stop thinking | ||
| supralapsarian | adj. | of the Calvinist doctrine that God’s predestination of some to eternal life and His condemnation of others to eternal damnation preceded (in some way) God’s decree of the Creation and the Fall of Man | ||
| supramundane | adj. | supermundane, elevated above or transcending the material world | British | |
| supremum | n. | least upper bound, smallest element of partially ordered set greater than or equal to every element of a subset of the partially ordered set | ||
| surcease | n. | cessation or stop, esp. when temporary | ||
| surcingle | n. | girth for horse or other animal that passes around belly and over pack, blanket, etc. to keep it in place | ||
| surd | n. | irrational number (esp. a root); voiceless consonant; [obsolete] deaf; stupid | ||
| surplice | n. | loose white linen overgarment worn by clergy and choristers | ||
| surrebuttal | n. | plaintiff’s response to a defendant’s rebuttal | ||
| susurration | n. | whisper; rustling | ||
| sutler | n. | merchant selling wares to soldiers in the field | ||
| suzerain | n. | state or ruler having control over dependent state | ||
| swad | n. | thick bunch or mass | ||
| swadkin | n. | diminutive of “swad” meaning country bumpkin, lout | ||
| swainmote | n. | one of the courts of the royal forest, with power over rights of agistment and pannage as well as ability to try offenders by a jury of forest swains | British | |
| swale | n. | low hollow, esp. marshy declivity between higher land | ||
| swank | v. | to swagger, to make pretense of superiority | ||
| sward | n. | surface of earth, usu. covered with herbage; grassy turf | ||
| swarf | n. | 1 | filings or fine grit from operation of grinder, axle, or other abrasive machining | |
| swarf | n. | 2 | fainting spell, swoon | Scots |
| swart | adj. | swarthy; dark in color | ||
| swathe | v. | to wrap in layers of material; to bandage | ||
| sweetbread | n. | thymus gland used as food; pancreas used as food | ||
| swing shift | n. | work shift between day shift and night shift; system wherein workers alternate between day and night tours of duty | ||
| swinge | v. | to flog, to thrash, to punish | archaic | |
| swingeing | adj. | large, great, severe, extreme | ||
| swink | v. | to labor, to work hard | ||
| swivet | n. | panic, state of excitement or anxiety | ||
| swizz | v. | to be disappointed, to be cheated | British | |
| swot | n. | hard work or study; diligent student | ||
| sybaritic | adj. | fond or overfond of luxurious pleasure | ||
| syllabub | n. | dessert of beaten and sweetened cream flavored with wine; drink of milk or cream mixed with wine or cider | ||
| syllogomania | n. | collectionism, compulsive hoarding, mental derangement characterized by obsessive collecting | ||
| sylph | n. | aerial spirit; slender girl or woman | ||
| synclinal | adj. | sloping downward | ||
| syncope | n. | fainting; sudden stopping, cutting short | ||
| syncretic | adj. | joining or reconciling diverse beliefs or practices | ||
| syndic | n. | governmental officer; official of corporation with plenipotentiary power to transact certain business | ||
| syndicalism | n. | movement espousing the transfer of control of the means of production and distribution to workers’ unions | ||
| synechia | n. | eye disease wherein the iris adheres to either the cornea or the lens |