A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

S Andromedae
S Doradus
S star
saccharin
Saccheri, Giovanni Girolamo (1667–1733)
sacculus
Sachs, Julius von (1832–1897)
Sacramento Peak Observatory
sacroiliac joint
sacrospinalis and semispinalis
sacrum
saddle
saddle joint
Sadr (Gamma Cygni)
saffron
Sagan, Carl Edward (1934–1996)
Sagdeyev, Roald Z. (1932–)
SAGE (Stratospheric Aerosol and Gas Experiment)
Sagitta (constellation)
sagittal crest
sagittal plane
Sagittarius (constellation)
Sagittarius A (Sgr A)
Sagittarius Arm
Sagittarius B2 (Sgr B2)
Sagittarius Dwarf Elliptical Galaxy
Sagittarius Dwarf Irregular Galaxy
St. Elmo's fire
St. Ives problem
St. Petersburg Paradox
Saha equation
sailing ships
Saiph (Kappa Orionis)
Sakharov, Andrei Dimitrievich (1921–1989)
Sakurai, Kunitomo (1933–)
Sakurai's Object
Salam, Abdus (1926–1996)
salicylic acid
salient
salinity
salinon
salivary glands
salmonella
Salpeter function
salt
salt dome
salt flat
salt lake
salt marshes and coastal swamps
Salyut
samarium
Samos
SAMPEX (Solar Anomalous and Magnetospheric Particle Explorer)
sample return mission
San Marco launch platform and satellites
sand
Sander, Friedrich Wilhelm (1885–1938)
sandstone
sandwich compound
Sänger, Eugen (1905–1964)
Sanger, Frederick (1918–2013)
sap
saponins
sapphire
saprophyte
Sarabhai, Vikram Ambalal (1919–1971)
sarcoidosis
sarcoma
Sargas (Theta Scorpii)
Sargasso Sea
Saros
sarsaparilla
SARSAT (Search and Rescue Satellites)
SAS (Small Astronomy Satellite)
Satcom
satellite
satellite galaxy
SATELLITES AND SPACE PROBES
saturated compound
saturation
Saturn
Saturn launch vehicles
Saturn Nebula (NGC 7009)
saurischian
savanna
Savery, Thomas (c. 1650–1715)
Savitskaya, Svetlana (1948–)
SBIRS (Space-Based Infrared System)
scalar
scalene muscles
scales
scalp
scandium
scapolite
scapula
scarlet fever
SCATHA (Spacecraft Charging At High Altitudes)
scatter ellipse
Scattered Disk
scattering
Scheele, Carl Wilhem (1742–1786)
scheelite
Scheiner, Christoph (1575–1650)
Scheiner, Julius (1858–1913)
Schiaparelli, Giovanni Virginio (1835–1910)
Schindleria brevipinguis (stout infantfish)
Schirra, Walter Marty, Jr. (1923–2007)
schist
schistosomiasis
Schläfli, Ludwig (1814–1895)
Schläfli symbol
Schmidlap, Johann (16th century)
Schmidt, (Johann Friedrich) Julius (1825–1884)
Schmidt, Maarten (1929–2022)
Schmidt camera
Schmidt-Cassegrain telescope
Schmiedl, Friedrich (1902–1994)
Schmitt, Harrison Hagan (1935–)
Schneider, William C.
Schönbein, Christian Friedrich (1799–1868)
Schõnberg-Chandrasekhar limit
Schottky barrier
Schrieffer, John Robert (1931–)
Schriever, Bernard A. (1910–2005)
Schröder's reversible staircase
Schrödinger, Erwin (1887–1961)
Schrödinger equation
Schroter, Johann Hieronymous (1745–1816)
Schultze, Max Johann Sigismund (1825–1874)
Schuster, Arthur (1851–1934)
Schwabe, (Samuel) Heinrich (1789–1875)
Schwann, Theodor (1810–1882)
Schwann cells
Schwarzschild, Karl (1873–1916)
Schwarzschild, Martin (1912–1997)
Schwarzschild black hole
Schwarzschild radius
Schwassmann-Wachmann 1, Comet 29P/
Schweikart, Russell L. (1935–)
Schwinger, Julius Seymour (1918–1994)
sciatic nerve
sciatica
SCIENCE CENTERS AND ATTRACTIONS
SCIENCE FICTION
science fiction involving extraterrestrials, up to 1900
science fiction involving extraterrestrials, 1900–1940
science fiction involving extraterrestrials, after 1940
science fiction involving extraterrestrials, in film and television
science in the eighteenth century
science in the Renaissance
SCIENCE OF STAR TREK
scientific instruments
scientific method
SCIENTIFIC MYSTERIES
scientific practical jokes
SCIENTIFIC SOCIETIES
scintillation
scintillation counter
sclera
sclerenchyma
sclerosis
scoliosis
scopolamine
SCORE (satellite)
scoria
18 Scorpii
scorpion
Scorpius (constellation)
Scorpius X-1
Scorpius-Centaurus Association
Scott, David R. (1932–)
Scout (rocket)
Scout Program (Mars)
scramjet
scree
screening
screw
scrofula
scrub typhus
Sculptor (constellation)
Sculptor Dwarf
Sculptor Group
scurvy
Scutum (constellation)
Scylla and Charybdis
SDS (Satellite Data System)
sea anemone
sea cucumber
sea fan
sea pen
sea snake
sea urchin
Seaborg, Glenn Theodore (1912–1999)
seafloor and seafloor spreading
SEALAB
seamount
seaplane
Search for Extraterrestrial Artifacts
Search for Extraterrestrial Intelligence
Search for Extraterrestrial Visitation
Seasat
seashore
seasonal affective disorder (SAD)
seasons
Seastar/SeaWiFS
seawater
seaweed
Seawinds
sebaceous gland
Secchi, Rev. Pietro Angelo (1818–1878)
second
second law of thermodynamics
secondary consumer
secondary emission
secondary growth
secondary mirror
SECOR (Sequential Collation of Range)
secretin
secular
sedative
Sedgwick, Adam (1785–1873)
sediment
sediment exploration station
sedimentary rock
sedimentation
Sedna
SEDS (Small Expendable-tether Deployer System)
Seebeck, Thomas Johann (1770–1831)
Seebeck effect
seed
Seeger, Charles L. (1912–2002)
seeing
segmented mirror
Segrè, Emilio Gino (1905–1989)
sei whale
seismic wave
seismograph
seismology
SELENE (Selenological and Engineering Explorer)
selenium
self-enumerating sentence
self-organization
self-organized criticality
self-repairing spacecraft
self-replicating probe
semaphore
semen
semicircular canals
semiconductor
semilunar valve
semipermeable membrane
semi-regular variable
semispinalis capitis
senses
sensor
sensory nerve
sensory receptor
sentinel hypothesis
Sentinel, Project
sepal
sepia
sepsis
septicemia
septum
septum nasi
sequence
sequence tagged site
séracs
sere
SERENDIP
Sergeant (missile)
series
series circuit
serotonin
serous gland
serous membrane
Serpens (constellation)
Serpens Dwarf
serpentine (curve)
serpentine (mineral)
serratus anterior and serrati posteriores
SERT (Space Electric Rocket Test)
serum
Servetus, Michael (1511–1553)
Serviss, Garrett (Putnam) (1851–1929)
servomechanism
sesamoid bone
sessile
set
set square
set theory
SETA (Search for Extraterrestrial Artifacts)
Setebos
SETI
SETI (Search for Extraterrestrial Intelligence)
SETI, false alarms
SETI, unexplained signals
SETI Institute
SETI League
SETI@home
SETIQuest magazine
SETS AND SET THEORY
setting circles
SETV (Search for Extraterrestrial Visitation)
seven
seventeen
sewing machine
sex chromosome
sexagesimal
Sextans (constellation)
Sextans Dwarf
sextant
Seyfert galaxy
Seyfert's Sextet (Hickson 79)
Sfera
SFU (Space Flyer Unit)
shadow
shadow transit
shale
Shannon, Claude Elwood (1916–2001)
Shapley, Harlow (1885–1972)
Shapley 1 (planetary nebula)
Shapley Concentration
shark
SHARP (Super High Altitude Research Project)
shatter cone
Shaula (Lambda Scorpii)
Shavit
Shedar (Alpha Cassiopeiae)
sheep
Sheffield plate
shell (electron)
shell burning
shell galaxy
shell star
Shenzhou
Shepard, Alan Bartlett, Jr. (1923–1998)
shepherd moon
sherardizing
shergottite
Sherrington, Charles Scott (1857–1952)
Shesta, John
shield (in geology)
shield (radiation)
shield volcano
shingles
Shinsei
ship
Shkadov thruster
Shklovskii, Iosif Samuilovich (1916–1985)
shock
shock front
shock wave
Shockley, William Bradford (1910–1989)
Shoemaker, Eugene Merle (1928–1997) and Carolyn Shoemaker (1929–2021)
Shoemaker-Levy 9, Comet (D/1993 F2)
short circuit
short-period comet
Shostak, Seth (1943–)
shotgun sequencing
shoulder
shrub
Shtil
shuffle
shunting puzzles
SI (Système Internationale) system of units
sial
sick sinus syndrome
sickle cell disease
sideband
sidereal time
siderite
siderophile element
Siding Spring Observatory
Siding Spring Survey
Siegbahn, Karl Manne Georg (1886–1978)
Siegel's paradox
siemens (unit)
Siemens brothers
Siemens-Martin open-hearth process
Sierpinski, Waclaw Franciszek (1882–1969)
Sierpinski number
sieve of Eratosthenes
sievert (unit)
sieve-tube
Sigma Draconis
Sigma Orionis star cluster
sigmoid colon
sigmoidoscopy
Sign, Project
signal verification
signal-to-noise ratio
significant figures
Sikhote-Alin meteorite
silane
silica
silicate
silicon
silicon-based life
silicone
silicosis
silique
silk
sill
sillimanite
silt
Silurian period
silver
Silver Coin Galaxy
Silverpit Crater
Silverstein, Abe (1908–2001)
sima
similar
simoom
simple harmonic motion
simple machine
simply-connected
Simpson, George Gaylord (1902–1984)
Simpson, James Young (1811–1870)
simultaneous equations
sine
Singer, Sigfried Frederick (1924–)
single-stage-to-orbit
singularity
sink hole
sinoatrial node
Sinope
sintering
Sinton, William M. (1925–2004)
sinus
siphon
Siphonaptera
siphuncle
Sipuncula
Sirenia
Sirius (Alpha Canis Majoris)
Sirius, mystery of red color
sirocco
sisal
Sitter, Willem de (1872–1934)
SIRTF
six
six circles theorem
skeletal muscle
skeletal muscle groups
skeletal system
skeleton
skeleton, differences between male and female
skepticism
Skewes' Number
skin
skin cancer
skin cancer treatment
skin disease
skull
skull, muscular attachments
Skull Nebula (NGC 246)
sky hook
Skyhook, Project
Skylab
Skylark
Skylon
Skynet
Skyrocket (Douglas)
slag
slate
Slayton, Donald Kent ("Deke") (1924–1993)
sleep
sleep apnea
sleeping sickness
slide rule
slime mold
sling-shot effect
Slipher, Earl C. (1883–1964)
Slipher, Vesto Melvin (1875–1969)
slipped disk
slope
Slothouber-Graatsma puzzle
slug
small intestine
Small Magellanic Cloud
smallpox
SMART-1
SMC X-1 (2U 0115-73)
SME (Solar Mesosphere Explorer)
smell
smelting
SMEX (Small Explorer)
Smith, William "Strata" (1769–1839)
Smith number
Smithson, James (1765–1829)
Smithsonian Institution
smithsonite
SMM (Solar Maximum Mission)
smog
smooth (mathematics)
smooth muscle
SMS (Synchronous Meteorological Satellite)
Smullyan, Raymond (1919–2017)
Smyth, Charles Piazzi (1819–1900)
snail
snakes, lizards, and turtles
snake bite
Snake Nebula (Barnard 72)
SNAP (Systems for Nuclear Auxiliary Power) and SNAPSHOT
Snark
SNC meteorites
SNOE (Student Nitric Oxide Explorer)
snow
snowball Earth
snowball prime
soaps and detergents
soapstone
Sobrero, Ascanio (1812–1888)
Socrates (c. 469–399 BC)
sodalite
Soddy, Frederick (1877–1956)
Soddy circle
Soddy's formula
sodium
sodium chloride
sodium-potassium pump
SOFIA (Stratospheric Observatory for Infrared Astronomy)
soft gamma repeater
soft palate
SOHO (Solar and Heliospheric Observatory)
soil
soil erosion
Sojourner
sol
Solar- (Japanese satellites)
solar apex
solar array
solar cell
solar conjunction
Solar Connections Initiative
solar constant
solar eclipse
solar flare
solar nebula
solar oxygenating pump
solar plexus
solar sail
solar system
solar system, formation
solar telescope
solar time
SOLAR TOPICS
solar wind
Solar-B
solar-electric propulsion
Solaris
solenoid
solfatara
solid (physics, chemistry)
solid angle
solid solution
solid state physics
SOLID STATE PHYSICS
SOLIDS AND SURFACES
solid-propellant rocket motor
solifuga
solipsism
soliton
Solrad (Solar Radiation program)
solstice
solubility
solubility product
solute
solution (chemistry)
solution (math)
Solvay process
solvent
Solwind
Soma Cube
somatic cell
somatostatin
somatotrophin
Sombrero Galaxy (M104, NGC 4594)
somite
Somnium
sonar
sonic boom
Sophie Germain prime
SORCE (Solar Radiation and Climate Experiment)
Sothic cycle
sound
sound barrier
sound recording
sounding rocket
source
South African Large Telescope
Southern Crab Nebula
Southern Pleiades (IC 2602)
Soxhlet apparatus
Soyuz
Soyuz launch vehicle
SP-100
space
Space 1999
space agencies
SPACE AND AEROSPACE MEDICINE
SPACE AND TIME
space ark
space cannon
space charge
space colony
SPACE CURVES
space drive
Space Electric Rocket Test
space elevator
Space Foundation
Space Frontier Foundation
Space Infrared Telescope Facility
Space Launch Initiative
space medicine
space motion sickness
Space Race
space sail
Space Science Board
Space Shuttle
space station
Space Station V (from 2001: A Space Odyssey)
Space Studies Board
Space Studies Institute
space survival
Space Technology 5
space tether
space tourism
Space Transportation System (STS)
Space Travel Argument
space velocity
SPACECRAFT
spacecraft, fastest
SPACECRAFT COMMUNICATION AND TRACKING
SPACECRAFT NAVIGATION AND CONTROL
SPACECRAFT TYPES
space-filling curve
Spaceguard Foundation
Spacehab
Spacelab
spaceplane
spaceport
Spaceport America
SpaceShipOne
spacesuit
spacetime
spacewalk
Spacewatch Project
Spadeadam Rocket Establishment
spadix
Spallanzani, Lazzaro (1729-1799)
spallation
SPARCLE (Space Readiness Coherent Lidar Experiment)
spark chamber
spark plug
sparrow
Spartan 201
SPAS (Shuttle Pallet Satellite)
spathe
spatter
spatter and cinder cone
spatter rampart
Special Astrophysical Observatory
special function
special theory of relativity
speciation
species
specific gravity
specific heat
SPECTRA AND SPECTROSCOPY
spectral lines
spectral series
spectral type
spectrophotometer
spectroscope
spectroscopic binary
spectroscopic companion
spectrum
Spectrum-X-Gamma
speech and speech disorders
speed
speed of light
speed of sound
Spemann, Hans (1869–1941)
Spencer, Herbert (1820–1903)
Spencer Jones, Harold (1890–1962)
sperm
sperm whale
spermatheca
spermatogenesis
spermatophore
spermatophyte
Sperner's lemma
Sperry, Elmer Ambrose (1860–1930)
sphagnum
sphalerite
sphenoid bone
sphere
sphere packing
spherical aberration
spherical astronomy
spherical coordinates
spherical geometry
sphericon
spheroid
spherometer
spherosome
sphincter
Sphinx riddle
sphygmomanometer
Spica (Alpha Virginis)
spicule
spices
spider
spider-and-fly problem
spiegeleisen
Spielberg, Steven (1947–)
spilite
spin
spin quantum number
spin stabilization
spin temperature
spina bifida
spinal column
spinal cord
spinal cord injury
spinal nerve
spindle
Spindle Galaxy (NGC 3115 and NGC 5866)
spinel
spinneret
spinning
spinor
Spinoza, Baruch (1632–1677)
spiral
spiral arm
spiral galaxy
spiracle
spirillum
spirochaete
spirogyra
spirometry
spit
Spitzer, Lyman (1914–1997)
Spitzer Space Telescope
Spitzer-Schwarzschild scattering mechanism
spleen
splenic artery
splenic vein
splenius
spodumene
sponge
spontaneous generation
spontaneous human combustion
spore
Spörer, Gustav Friedrich Wilhem (1822–1895)
Spörer minimum
Spörer's law
sporophyte
SPOT (Satellite Probatoire d'Observation de la Terre)
Sprague-Grundy theory
spring (device)
spring (water)
sprite
s-process
Sproul Observatory
Sprouts
Spruce Goose
Sputnik
Sputnik launch vehicle
squall
Squamata
square
square free
Square Kilometer Array
square number
Square of Pegasus
square root of 2
squaring the circle
squaring the square
squark
squid
Sriharikota High-Altitude Range Centre
SRTM (Shuttle Radar Topography Mission)
SS (Scientific Satellite)
SS 433
SS Cygni
SSS (Small Scientific Satellite)
stabilizer (aerodynamics)
stabilization of satellites
stable equilibrium
stack
Stack, John (1906–1972)
Stacksat
Stafford, Thomas P. (1930–)
staging
Stahl, Georg Ernest (1660–1734)
stalactites and stalagmites
stamen
standard candle
standard deviation
standard electrode
standard form
standard model
standard solution
standard star
standard temperature and pressure (STP)
standing wave
Stanhope, Earl
Staphylococcus
Stapledon, (William) Olaf (1886–1950)
Stapp, John Paul (1910–1999)
STAR (Self-Testing and Repairing computer)
star
star cluster
star diagonal
star drive
Star Maker
Star of David
Star of Lakshmi
star streaming
Star Trek
Star Wars
starburst galaxy
starch
Stardust
starfish (echinoderm)
Starfish (satellites)
Stargazer, Project
Stark, Johannes (1874–1957)
Stark effect
STARS, BRIGHTEST
stars, classification
stars, evolution
stars, lifetimes
STARS, NOTABLE
stars, masses
STARS, NEAREST
stars, numbers
stars, populations
stars, sizes
stars, temperatures
STARS, TYPES
STARSHINE (Student Tracked Atmospheric Research Satellite for Heuristic International Networking Equipment)
starship
START (Spacecraft Technology and Advanced Reentry Test)
Start-1 Russian launch vehicle
state of matter
STATES OF MATTER
static electricity
statics
stationary point
station-keeping
statistical mechanics
statistical parallax
statistics
STATISTICS AND PROBABILITY
Staudinger, Hermann (1881–1965)
staurolite
steady-state theory
stealth technology
steam
steam distillation
steam engine
stearic acid
STEDI (Student Explorer Demonstration Initiative)
steel
Stefan-Boltzmann law
Steiner, Jakob (1796–1863)
Steiner-Lehmus theorem
Steinhaus, Hugo Dyonizy (1887–1972)
Steinmetz, Charles Proteus (1865–1923)
stele
Stella
stellar association
STELLAR ASTROPHYSICS
stellar atmosphere
stellar engine
stellar evolution
stellar wind
stellation
stem
stem cell
Stennis Space Center (SSC)
Steno, Nicolaus (1638–1686)
stent
STENTOR
step principle
Stephan's Quintet
Stephano
Stephenson family
steppes
steradian
STEREO (Solar TErrestrial RElations Observatory)
stereochemistry
stereoisomers
stereoscope
sterile neutrino
Stern, Otto (1888–1969)
Sternberg State Astronomical Institute
sternoclavicular joint
sternomastoid muscle
sternum
steroid
sterol
stethoscope
Stevens family
Stevinus, Simon (1548–1620)
Steward Observatory
Stewart, Dugald (1753–1828)
Stewart, Homer J. (1915–2007)
Stewart Committee
Stewart toroid
STEX (Space Technology Experiments)
stibnite
stigma
Still, Andrew Taylor (1828–1917)
stimulant
stipule
stishovite
stochastic process
Stokes, George Gabriel (1819–1903)
Stokes' law
stolon
stoma
stomach
Stoney, G. Johnstone (1826–1911)
stony meteorite
stony-iron meteorite
storm
straight
strain
strait
Strand, Kay Aage Gunnar (1907–2000)
strange particle
strangeness and strange particles
strap-on booster
Strassmann, Fritz (1902–1980)
strategy
stratigraphic column
stratigraphy
stratosphere
stratovolcano
stratum
strawberry
streamlining
Strela
strep throat
Strepsiptera
streptococcus
streptomycin
stress
stress testing
stressed limits
strewn field
string
string puzzle
string theory
strobogrammatic prime
stroboscope
stroke
stromatolite
Strombolian eruption
Strömgren, Bengt Georg Daniel (1908–1987)
Strömgren sphere
strong force
strontianite
strontium
strophoid
structural isomers
Strughold, Hubertus (1898–1987)
Struve, Friedrich Georg Wilhelm von (1793–1864)
Struve, Otto (1897–1963)
Struve, Otto Wilhelm (1819–1905)
Struve 2398
Struve's Lost Nebula (NGC 1554)
STRV (Space Technology Research Vehicle)
strychnine
stub fins
student's t-distribution
Stuhlinger, Ernst (1913–2008)
Sturgeon, William (1783–1850)
sturgeons
style
stylopharyngeus
S-type asteroid
styrene
SU Ursae Majoris star
Subaru Telescope
subcarrier
subclavian artery
subclavian vein
subclavius
subcutaneous tissue
subduction
subdwarf
subgiant
sublime
sublime number
submarine
Submillimeter Array
submillimeter band
Submillimeter Telescope Observatory
submillimeter wave astronomy
suborbital
subset
subshell
subsolar point
subsonic
subspace
substantia nigra
substitution cipher
substitution reaction
substorm
substrate
subtraction
subway
succession
succinic acid
succulent
sucrase
sucrose
Sudbury Crater
Sudbury Neutrino Observatory
sudden cardiac arrest
sugar
suicide gene
Suisei
"Suitcase SETI"
sulfate
sulfide
sulfite
sulfonamide
sulfonation
sulfonic acid
sulfur
sulfur dioxide
sulfur trioxide
sulfuric acid
Sullivan, Kathryn D. (1951–)
Sultan's Dowry
Summer Triangle
Sumner, James Batcheller (1887–1955)
Sun
SUN AND RELATED TOPICS
Sun, as a gravitational lens for focusing interstellar signals
Sun, life on
sunburn
sundial
Sunflower Galaxy (M63, NGC 5055)
sun-grazing comet
Sun-like stars
sunspot
sunstroke
sun-synchronous orbit
Sunyaev-Zel'dovich effect
superbubble
supercivilizations
supercluster
supercomputer
superconductivity
supercooling and superheating
super-Earth
superegg
superellipse
superficial fascia
superfluidity
superfactorial
superflare
supergalactic plane
supergiant
supergranulation cell
supergravity
super-hump
superior mesenteric artery
superior thyroid artery
superior vena cava
Super-Kamiokande
superluminal radio source
supermassive black hole
supermoon
supernova
supernova 1987A
supernova imposter
supernova remnant
superorganism
super-outburst
superoxide
superparticle
super-rotation
supersonic
superstring theory
supersymmetry
supine g
supramolecular chemistry
suprascapular artery
surd
surface
surface anatomy
surface brightness
surface energy
surface gravity
surface integral
surface of revolution
surface tension
SURFSAT (Summer Undergraduate Research Fellowship Satellite)
surge
surgery through the ages
surreal number
surveillance satellite
Surveyor
Surveyor 3
survival, in space
suspended animation
suspensory ligaments
sustainer engine
suture
Svobodny Cosmodrome
Swan bands
Swarm (spacecraft)
SWAS (Submillimeter Wave Astronomy Satellite)
sweat gland
Swedenborg, Emanuel (1688–1772)
Swift, Jonathan and the moons of Mars
Swift Gamma-Ray Burst Explorer
Swift-Tuttle, Comet 109P/
Swigert, John Leonard (Jack), Jr. (1931–1982)
swim bladder
swing-wing aircraft
SX Arietis star
SX Phoenicis star
Sycorax
Sydenham, Thomas (1624–1689)
Sylvester, James Joseph (1814–1897)
symbiosis
symbiotic star
symmedian
symmetric group
symmetry
symmetry group
sympathetic nervous system
synapse
synchronous rotation
synchrotron
synchrotron radiation
Syncom
syndrome
synergic curve
synodic
synodic period
synovial fluid
synovial joint
synovial membrane
synovial sheath
synthetic aperture radar
syphilis
syringe
Syromiatnikov, Vladimir S. (1933–2006)
Syrtis Major
system
SYSTEMS THEORY
syzygy
Szilard, Leo (1898–1964)
Szilassi polyhedron