Sporadic cancerCancer that occurs randomly and is not inherited from parents. Caused by DNA changes in one cell that grows and divides, spreading throughout the body.
Sporadic EIn solar-terrestrial terms, a phenomenon occurring in the E region of the ionosphere, which significantly affects HF radiowave propagation.
sporangium(pl.: sporangia) A reproductive structure in plants that produces spores. A megasporangium produces megaspores, which give rise to the female gametophyte…
SporeA term used to describe a particle in plants, bacteria and fungi.
sporophyteThe diploid generation in the life cycle of a plant, and that produces haploid spores by meiosis.
SporozoiteA stage in the life cycle of the malaria parasite. Sporozoites are produced in the mosquito and migrate to the mosquito's salivary glands.
Sporozoite rateThe proportion of female anopheline mosquitoes of a particular species that have sporozoites in their salivary glands (as seen by dissection), or that are…
sportAn individual plant, or portion thereof, showing a recognizably different phenotype from the parent, presumably as a result of spontaneous mutation.
SportingShowing good sportsmanship and ethics in pursuit of game fish.
SPOTSysteme Probatoire dObservation de la Terre - French observation satellite
spot beamIn satellite communications systems, a narrow beam from a satellite station antenna that illuminates, with high irradiance, a limited area of the Earth by…
Spot InstanceA purchase option available to AWS users. In essense, users can bid on spare Amazon EC2 instances and purchase them if their bid exceeds the current Spot…
spot jammingThe jamming of a specific channel or frequency. [JP 1-02]
Spot marketCommodities and foreign currencies are traded for immediate delivery and payment on the spot market, also known as a cash market.
Spot priceThe spot, or cash, price is the price of commodities and foreign currencies that are being sold for immediate delivery with payment in cash.
spot projectionIn facsimile systems, optical scanning in which a scanning spot is moved across the object and the scanning spot size is determined by the illuminated…
spot sizeThe size of the electron spot on the face of a cathode ray tube. Note: The spot size is larger than the diameter of the electron beam because of the…
spot speedIn facsimile systems, the speed of the scanning or recording spot along the available line.
SPOTNILIn solar-terrestrial terms, a spotless disk.
Spotted owl habitatDispersal habitat: Forest vegetation with at least 40% canopy closure and an average stand diameter of 11".
spotted thistle(... THIH-sel) A plant whose leaves, stems, and flowers have been used in some cultures to treat certain medical problems.
SpottingOutbreak of secondary fires as firebrands or other burning materials are carried ahead of the main fire line by winds.
SpouseLegally married husband or wife. A co-habiting partner does not qualify as a spouse for immigration purposes.
SPR(1) Secretarial Program Review (AF). (2) Secretarial Performance Review (OSD). (3) Sponsors Program Review (Navy).
SprawlDevelopment patterns where rural land is converted to urban/suburban uses more quickly than needed to house new residents and support new businesses, and…
SprayAn ensemble of water droplets torn by the wind from an extensive body of water, generally from the crests of waves, and carried up into the air in such…
Spray PyrolysisA deposition process whereby heat is used to break molecules into elemental sources that are then spray deposited on a substrate.
SpreadIn the most general sense, a spread is the difference between two similar measures.
spread spectrumTelecommunications techniques in which a signal is transmitted in a bandwidth considerably greater than the frequency content of the original information.
Spread tradingBuying one instrument/commodity and selling another, with a view to profiting from the change in the gap between the two markets.
Spread-limitA betting structure in which a player may bet any amount in a range on every betting round.
Spreader StockerA type of furnace in which fuel is spread, automatically or mechanically, across the furnace grate.
Spreader stoker furnaceA furnace in which fuel is automatically or mechanically spread. Part of the fuel is burned in suspension. Large pieces fall on a grate.
SpringThe point at which the water table meets Earth's surface, causing water to flow from the ground.
Spring Line (Backing Line)A line, used in mooring, to hold the boat from running upstream. The lines cross one another.
Spring TideA tide higher than normal which occurs around the time of the new and full moon.
SpringlineAn imaginary horizontal reference line located at midheight, or halfway point, of a circular conduit, pipe, tunnel, or the point at which the side walls…
Sprinkler irrigationA method of irrigation in which the water is sprayed, or sprinkled, through the air to the ground surface.
Sprinkler systemConsists of pipelines which carry water under pressure from a pump or elevated source to lateral lines along which sprinkler heads are spaced at…
SprintNuclear-armed, short-range interceptor used in SAFEGUARD/Sentinel systems.
spurA secondary route having a junction to the primary route in a network.
spurious emissionEmission on a frequency or frequencies which are outside the necessary bandwidth and the level of which may be reduced without affecting the corresponding…
spurious noiseCircuit noise or interference that is like a signal. [T1.401-1988]
spurious responseIn radio reception, a response in the receiver intermediate frequency (IF) stage produced by an undesired emission in which the fundamental frequency (or…
spurious tonesAny tone that (a) is other than a fundamental tone or its harmonics, and (b) is generated within the back-to-back connected transmit and receive terminal…
SputteringA process used to apply photovoltaic semi-conductor material to a substrate by a physical vapor deposition process where high-energy ions are used to…
sputum(SPYOO-tum) Mucus and other matter brought up from the lungs by coughing.
sputum cytology(SPYOO-tum sy-TAH-loh-jee) Examination under a microscope of cells found in sputum (mucus and other matter brought up from the lungs by coughing).
SQL (Structured Query Language)a standard fourth generation programming language (4GL - a programming language that is closer to natural language and easier to work with than a…
SQL Server computerA computer with an installed configuration of Microsoft SQL Server with a configured database.
SQL/JA set of standards that includes specifications for embedding SQL statements in methods in the Java programming language and specifications for calling…
SQL/MMAn international standards effort, sponsored by ISO to extend SQL to support multimedia applications, including access and manipulation of geographic data.
squalamine lactateA drug that belongs to the family of drugs called angiogenesis inhibitors. It prevents the growth of new blood vessels into a solid tumor.
SquallA strong wind characterized by a sudden onset in which the wind speed increases at least 16 knots and is sustained at 22 knots or more for at least one…
Squall LineA line of active thunderstorms, either continuous or with breaks, including contiguous precipitation areas resulting from the existence of the…
squamous cell(SKWAY-mus sel) Flat cell that looks like a fish scale under a microscope. These cells cover inside and outside surfaces of the body.
squamous cell carcinoma(SKWAY-mus sel KAR-sih-NOH-muh) Cancer that begins in squamous cells, which are thin, flat cells that look like fish scales.
squamous cell carcinoma of the head and neck(SKWAY-mus sel KAR-sih-NOH-muh â¦) Cancer of the head and neck that begins in squamous cells (thin, flat cells that form the surface of the…
squamous intraepithelial lesion(SKWAY-mus IN-truh-eh-pih-THEEL-ee-ul LEE-zhun) A general term for the abnormal growth of squamous cells on the surface of the cervix.
SquareA unit of land defined by the DC Surveyor that normally consists of a single city block and contains record and tax lots.
square pixelA pixel of equal width and height; i.e., having an aspect ratio of 1:1 Note: Pixels created by computer graphics usually have an aspect ratio of 1:1.
square waveA wave that has two significant conditions, i.e., two levels of amplitude, that change from one condition to the other in a relatively short time compared…
Square Wave InverterA type of inverter that produces square wave output.; consists of a DC source, four switches, and the load.
SquaresA game that is on the level or honest; or a player who is on the level or honest.
squelchA circuit function that acts to suppress the audio output of a receiver. [NTIA] Note: The squelch function is activated in the absence of a sufficiently…
SquidooTopical lens site created by Seth Godin. See also: Squidoo.com
Squirrel Cage MotorThis is another name for an induction motor. The motors consist of a rotor inside a stator.
SR-29142A drug that may protect healthy tissue from the toxic effects of anticancer drugs.
SR-45023AAn anticancer drug that belongs to the family of drugs called bisphosphonates. It affects cancer cell receptors governing cell growth and cell death.
SR49059A substance being studied in the treatment of cancer. It inhibits a hormone growth factor that causes some cancer cells to divide.