All articles A–Z

Spatial sampling design

Spatial sampling design is the set of procedures for choosing which locations to observe in a geographically distributed population, organized around design-based and model-based inference.

Spatial transcriptomics

Spatial transcriptomics is a family of molecular biology methods that maps gene expression across intact tissue while recording each transcript's position, introduced by Patrik Ståhl in 2016.

Spatially fractionated radiation therapy

Spatially fractionated radiation therapy (SFRT) is a radiotherapy technique delivering high-dose peaks separated by low-dose valleys to shrink bulky tumors, including 2D GRID therapy and 3D lattice radiotherapy.

Spatially offset Raman spectroscopy

Spatially offset Raman spectroscopy (SORS) is a technique that collects Raman light away from the laser spot, chemically analyzing buried layers and sealed containers without sample preparation.

Spatially resolved spectroscopy

Spatially resolved spectroscopy records a spectrum at every location across a sample, turning variation in composition or structure into an image rather than a bulk average.

Spatio-temporal clustering

Spatio-temporal clustering is a data mining method that groups points close in both space and time, applied to GPS tracks, crime hotspots, and Twitter event detection.

Spatio-temporal data mining

Spatio-temporal data mining (STDM) extracts useful patterns from large datasets where every measurement carries a location and a timestamp, such as GPS trajectories, sensor readings, and evolving weather maps.

Spatiotemporal graph convolutional network

A spatiotemporal graph convolutional network (STGCN) is a neural architecture combining graph convolutions over sensor networks with temporal convolutions, introduced in 2018 for traffic forecasting and skeleton-based action recognition.

Spatiotemporal mode-locking

Spatiotemporal mode-locking is a regime of laser operation in which the spatial and temporal modes of a resonator lock simultaneously, demonstrated in multimode fiber lasers by Wright, Christodoulides, and Wise in 2017.

Spatiotemporal modulation

Spatiotemporal modulation is a wave-engineering technique in which material properties such as stiffness or permittivity vary in space and time, breaking reciprocity without magnetic biasing or nonlinearity.

Spatiotemporal modulation in metasurfaces

Spatiotemporal modulation in metasurfaces is the variation of a metasurface's parameters in space and time, letting it change a wave's direction and frequency and break reciprocity.

Spatiotemporal modulation nonreciprocity

Spatiotemporal modulation nonreciprocity is a technique for breaking Lorentz reciprocity in optics by modulating a material in space and time, giving waves a preferred direction of travel.

Spatiotemporal optical vortices

Spatiotemporal optical vortices (STOVs) are structured light pulses whose phase winds helically in a space-time plane, giving them transverse orbital angular momentum, first observed in filamentating femtosecond pulses in 2016.

Spats (footwear)

Spats are buttoned shoe coverings, short for spatterdashes, that keep shoes and ankles clean; they were a fashionable men's accessory from about 1910 to the mid-1930s.

Spatula

Spatula: a broad, flat, unsharpened blade on a handle for lifting, turning, spreading, or scraping food; also called turner, flipper, or fish slice. From Latin spatula via Greek spathe; types include turners, scrapers, and fish spatulas in silicone, steel, nylon, or wood.

Spätzle

Spätzle (Schwäbische Spätzle/Schwäbische Knöpfle) are small Central European egg noodles or dumplings from a soft flour-egg batter, scraped or pressed into boiling water; a Swabian staple with PGI protection since 2012.

Oct 21, 2026

Spava

Spava names two games: a 2012 two-player Shibumi abstract board game by Cameron Browne (Spline plus Yavalath's N-but-not-N−1 rule) and a 2024 UncleReed hidden-object Steam game.

Spawn (1997 film)

Spawn (1997 film): New Line Cinema superhero horror film directed by Mark A.Z. Dippé, based on Todd McFarlane's comic, starring Michael Jai White and John Leguizamo; grossed over $100 million but was panned by critics.

Spawn (character)

Spawn (Al Simmons) is the Image Comics anti-hero created by Todd McFarlane, debuting May 1992; a Hellspawn soldier of Malebolgia powered by finite necroplasm, star of the best-selling (1.7 million copies) and longest-running independent comic series.

SPD Healthcare (思派健康)

SPD Healthcare, or Sipai Health Technology (思派健康), is a Beijing health-technology company founded in 2014 by former Bayer executives Ma Xuguang and Li Ji, once China's largest private specialty pharmacy.

Oct 15, 2026

SPDX

SPDX (System Package Data Exchange) is a Linux Foundation open standard for software bill of materials data, covering licenses, dependencies, and security, and published as ISO/IEC 5962:2021.

Oct 15, 2026

SPE Petroleum Resources Management System

The SPE Petroleum Resources Management System (PRMS) is the worldwide standard for classifying oil and gas reserves and resources, first issued in 2007 and updated in 2018.

Speak (Anderson novel)

Speak (1999) is Laurie Halse Anderson's debut young adult novel about Melinda Sordino, a ninth grader rendered nearly mute after being raped by an upperclassman; a National Book Award finalist and Printz Honor book, frequently taught and frequently banned.

Speak & Spell (album)

Speak & Spell is the 1981 debut studio album by Depeche Mode, released on Mute Records; the only one written mostly by Vince Clarke, featuring Just Can't Get Enough, recorded at Blackwing Studios, and followed by Clarke's departure.

Speak English or Die

Speak English or Die is the 1985 Megaforce debut album by crossover thrash band Stormtroopers of Death (S.O.D.), the Anthrax side project of Scott Ian, Charlie Benante, Dan Lilker, and Billy Milano: 21 songs in under 29 minutes, recorded in three days.