Technology glossary

Soft Magnetic Composite

A material made from magnetic particles separated by electrically insulating layers. It is designed to magnetize and demagnetize easily while allowing three-dimensional magnetic paths and limiting eddy-current losses.

Soft Robotics

A field of robotics that builds machines from flexible, compliant, or deformable materials rather than relying only on rigid links and joints. Soft robots can adapt to irregular shapes and interact more gently with people or delicate objects, though precise control can be challenging.

Solar Corona

The Sun's faint outer atmosphere, normally invisible against the Sun's direct glare but visible to the naked eye during the brief moments of a total solar eclipse.

Solid Oxide Cell

An electrochemical device that uses a solid ceramic material to conduct oxygen ions at high temperature, letting it either generate electricity from hydrogen or split water into hydrogen depending on how it is operated.

Solid-state battery

A rechargeable battery that uses a solid electrolyte to conduct ions between its electrodes instead of a liquid electrolyte. Performance depends on the electrolyte chemistry and the quality of contact between solid components. A solid electrolyte does not by itself guarantee higher energy density, faster charging, or operation at extreme temperatures.

Solvent Engineering

The deliberate selection, formulation, or control of solvents to influence a chemical process or the properties of a manufactured material. It can affect solubility, reaction rates, crystal growth, film formation, safety, and environmental impact.

Space-Based Computing

Computing performed aboard satellites, spacecraft, or other orbital platforms rather than exclusively on Earth. It can support navigation, scientific analysis, communications, and rapid processing of data close to where it is collected.

Sparse Coding

A representation strategy in which each input activates only a small subset of available units, reducing overlap and computational activity.

Spatial Transcriptomics

A family of methods that measures gene activity while preserving information about where cells or signals sit within tissue. It helps researchers map cellular neighbourhoods that may be missed when a sample is mixed and analysed in bulk.

Specific Impulse(Isp)

A measure of rocket-engine propellant efficiency, defined as thrust produced per unit weight flow of propellant and commonly expressed in seconds. A higher specific impulse means more thrust can be obtained from a given amount of propellant, but it does not by itself indicate total thrust or engine power.

Specific On-Resistance(RON,sp)

A power device's electrical resistance while conducting, normalized by active area. Lower values generally mean less conduction loss for a given chip area.

Spiking Neural Network(SNN)

A neural network whose simulated neurons communicate with discrete spikes over time, allowing information processing to depend on both which neurons fire and when they fire.

Spin Qubit

A qubit that stores quantum information in the spin state of an electron or another particle.

Spiropyran

A class of light-responsive organic molecules that can switch between a compact closed form and a more open form. This molecular switch is used in smart materials, optical sensors and photoresponsive polymers.

Sprint Interval Training(SIT)

An exercise method built from repeated, very short bouts performed at or near maximal effort, separated by recovery periods. It differs from high-intensity interval training because sprint intervals typically demand all-out effort rather than a fixed submaximal intensity.

Squawk Code

A four-digit code entered into an aircraft transponder so air traffic control can identify the flight or recognise a special condition such as an emergency.

Sst-Chodl Neuron

A rare somatostatin-expressing inhibitory neuron distinguished by Chodl expression and unusually long cortical projections. In mice, these cells become active during deep sleep and can help synchronize distant neocortical regions.

Stablecoin

A cryptoasset designed to track a reference value, commonly a national currency such as the US dollar. Stability depends on the issuer's reserves, redemption arrangements, market structure or algorithm, so the price is not guaranteed to remain fixed in every circumstance.

Stellar Spectroscopy

The measurement of a star's light after separating it by wavelength. Absorption and emission patterns reveal chemical elements, temperature, motion, gravity, and other physical properties that cannot be seen in an ordinary image.

Stereolithography(SLA)

A 3D-printing process that uses controlled light to cure liquid photopolymer resin layer by layer into a solid object.

Stratospheric Smoke Injection

The transport of wildfire smoke above the troposphere into the stratosphere, where it can persist longer and influence atmospheric chemistry and climate.

Strike Zone

The defined space above home plate used to decide whether a baseball pitch is called a strike when the batter does not swing.

Strontium-Calcium Ratio(Sr/Ca)

A chemical ratio in coral skeletons that varies with seawater temperature and can be calibrated as a paleoclimate thermometer.

Structural Color

Colour produced when microscopic or nanoscale structures selectively scatter, reflect or interfere with light, rather than when molecules absorb wavelengths as conventional pigments do. Its appearance depends on the structure's dimensions, material and arrangement.

Subglacial Exploration

The investigation of environments beneath glaciers or ice sheets, including bedrock, sediments, water networks, and lakes. Researchers use drilling, radar, seismic methods, sensors, and robotic vehicles while applying strict controls to avoid contaminating isolated environments.

Subthreshold Swing(SS)

The change in gate voltage required to increase a transistor's drain current by a factor of ten while it is turning on. A smaller value means sharper switching and can help lower supply voltage and energy use.

Summary Judgment

A court decision issued without a full trial when no material factual dispute requires a jury or fact-finder to resolve it.

Super Peer

A highly reachable node in a peer-to-peer network that helps other nodes discover participants, route information or maintain connectivity without a central server.

Super-Eddington Accretion

The inflow of matter onto a compact object at a rate above the conventional Eddington limit, where outward radiation pressure would normally balance gravity. Thick gas can trap or redirect radiation, allowing faster growth for a time.

Superconducting Qubit

A quantum bit implemented with electrical circuits made from superconducting materials and interrupted by Josephson junctions. At very low temperatures, selected circuit energy states represent 0 and 1 and can be controlled with microwave pulses, though noise and material defects limit coherence.