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Spektrum RC
Spektrum RC is a Horizon Hobby brand of 2.4GHz radio equipment for model aircraft, helicopters, and surface vehicles, which introduced DSM spread-spectrum technology in 2004.
SPEL (robot language)
SPEL, formally SPEL+, is the proprietary structured programming language Seiko Epson supplies for its industrial SCARA and 6-axis robots, executed through the Epson RC+ development environment.
Speleogenesis
Speleogenesis is the origin and development of caves by dissolution of soluble rock. Two modes: epigenic (surface carbonic acid, e.g., Mammoth Cave) and hypogenic (deep fluids, e.g., sulfuric acid caves like Carlsbad Cavern and Lechuguilla).
Speleology
Speleology is the scientific study of caves, covering their formation, geology, hydrology, biology, and the exploration techniques, with roots dating to late 19th-century cave surveying.
Speleomantes
Speleomantes (European cave salamanders), genus Dubois 1984, eight lungless plethodontid species: three in mainland Italy/France, five endemic to Sardinia; sister to Californian Hydromantes, diverged late Oligocene; Atylodes is a synonym.
Speleothem
Speleothem: secondary mineral deposits formed in caves, chiefly calcite stalactites, stalagmites, flowstone, and columns. Distinguished by morphology rather than composition; key climate archives dated by U-Th and U-Pb methods.
Speleothems as paleoclimate archives
Speleothems, cave formations such as stalagmites, preserve dated records of past rainfall, temperature, and vegetation, and are among the most precisely dated terrestrial climate archives available.
Speleotherapy
Speleotherapy is the therapeutic use of the microclimate of caves and mines for chronic airway diseases such as asthma, widely practiced in Central and Eastern Europe.
Spell checker
A spell checker is software that identifies misspelled words and suggests corrections, found in word processors, browsers, and search engines since Ralph Gorin's 1971 SPELL program.
Spell of the Twelve Caves
The Spell of the Twelve Caves, or Book of the Twelve Caverns, is an Egyptian funerary text listing the deities of the twelve caverns of the underworld.
Spellbound (1945 film)
Spellbound (1945) is Alfred Hitchcock's psychological thriller starring Ingrid Bergman and Gregory Peck, produced by David O. Selznick, with a Salvador Dalí-designed dream sequence and Miklós Rózsa's Oscar-winning theremin score, based on The House of Dr. Edwardes.
Spellbound (2002 film)
Spellbound (2002) is Jeffrey Blitz's Oscar-nominated documentary following eight children, including winner Nupur Lala, through the 1999 Scripps National Spelling Bee; it grossed $5.7 million and won an Emmy.
Spellbound (2024 film)
Spellbound (2024) is a Netflix animated musical from Skydance Animation, directed by Vicky Jenson, with songs by Alan Menken and Glenn Slater. Princess Ellian (Rachel Zegler) seeks to restore her monster-transformed parents (Nicole Kidman, Javier Bardem); released November 22, 2024.
Spelling
Spelling, the conventional written forms of a language's words, here chiefly English orthography: Old English was fairly phonemic, but the Norman Conquest, printing, and the Great Vowel Shift left English the most irregular alphabetic spelling system, resistant to reform since Johnson and Webster.
Spelling alphabet
A spelling alphabet, also called a radiotelephony or phonetic alphabet, is a fixed set of code words, one per letter, used to spell words clearly over radio and telephone.
Spelling bee
Spelling bee: oral spelling competition, mainly American, in which students spell words aloud until one remains. Best known via the Scripps National Spelling Bee (since 1925); 2026 champion Shrey Parikh set a spell-off record of 32 words in 90 seconds.
Spelling correction
Spelling correction is the automatic detection of misspelled words in text and selection of a replacement, a natural language processing task dating to the early 1960s.
Spelman College
Spelman College, formerly Atlanta Baptist Female Seminary and Spelman Seminary, is a private historically Black women's liberal arts college in Atlanta, Georgia, founded in 1881.
Spelt
Spelt, also known as Triticum spelta or Dinkel wheat, is a hulled wheat grown as a cereal crop and a major bread grain in Central Europe into the 20th century.
Spelunky
Spelunky: Derek Yu's roguelike-inspired 2D platformer, freeware in 2008, HD on XBLA July 4, 2012; procedurally generated levels, permadeath, Metacritic 87, sequel Spelunky 2 in 2020.
Spemann-Mangold organizer
Spemann-Mangold organizer (Spemann organizer): amphibian dorsal blastopore lip inducing a secondary embryonic axis; discovered by Spemann and Mangold in 1924; signals via BMP, Wnt, and Nodal antagonists such as Chordin and Noggin.
Spence (mine)
Spence is a large open-pit copper mine in the Atacama Desert of northern Chile, wholly owned and operated by BHP, producing copper cathode and concentrates since 2006.
Spencer (film)
Spencer (2021) is a psychological drama directed by Pablo Larraín, written by Steven Knight, starring Kristen Stewart as Diana, Princess of Wales, imagining her 1991 Christmas at Sandringham as she decides to leave Prince Charles; Venice premiere, Oscar-nominated performance.
Spencer 1882
The Spencer 1882 is a 12-gauge pump-action shotgun designed by Christopher Spencer and Sylvester Roper, patented in 1882 and recognized as the first commercially successful, mass-produced pump-action shotgun.
Spencer Arrighetti
Spencer Arrighetti (born 2000) is an MLB right-handed pitcher, drafted by Houston in 2021, 2024 Astros Rookie of the Year, traded to the Toronto Blue Jays in August 2026 for Daulton Varsho.
Spencer B. King
Spencer B. King is an American interventional cardiologist in Atlanta who led the EAST trial of angioplasty versus bypass surgery and built Emory's interventional cardiology program.
Spencer Bloch
Spencer Janney Bloch, born in 1944, is an American mathematician and emeritus professor at the University of Chicago known for algebraic cycles, higher K-theory, and the Bloch–Kato conjectures.
Spencer Breslin
Spencer Breslin (born 1992, New York) is an American actor and producer, older brother of Abigail Breslin, known for Disney's The Kid, The Santa Clause 2/3, The Cat in the Hat, and later independent films.
Spencer Cox
Spencer J. Cox is an American Republican politician who has served as the 18th governor of Utah since 2021, after being lieutenant governor from 2013.
Spencer Danielson
Spencer Danielson, Boise State Broncos head football coach since December 2023, former defensive coordinator; won three straight Mountain West titles, led 2024 College Football Playoff run, extended through 2030.