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SpaceX Starship
SpaceX Starship, also called the Starship and Super Heavy, is a fully reusable two-stage super-heavy-lift rocket developed by SpaceX at Starbase, Texas, and selected by NASA for the Artemis lunar landings.
SpaceX Starship design history
The SpaceX Starship design history traces the fully reusable Super Heavy booster and Starship spacecraft from 2012 Mars studies through the ITS, BFR, and V3 vehicles.
Spacing effect
Spacing effect (distributed practice, spaced repetition): long-term memory improves when study sessions are separated in time rather than massed. First studied by Ebbinghaus (1885); meta-analyses show moderate effects (d ≈ 0.46–0.85) across classroom, language, math, and medical learning.
Spacing Guild
Spacing Guild: fictional Dune organization holding a monopoly on interstellar travel via spice-mutated Navigators with limited prescience guiding Heighliners through foldspace; one leg of the Great Convention tripod, later broken by Ixian navigation machines.
SpaCOVID trial
The SpaCOVID trial was a completed randomized clinical trial at Comenius University in Bratislava testing mountain spa rehabilitation, with or without ubiquinol, for post-COVID-19 syndrome.
spaCy
spaCy is an open-source natural language processing library for Python and Cython, first released in 2015 by Explosion, with pretrained pipelines supporting tagging, parsing, and named entity recognition in over 70 languages.
SPAD (railway)
A signal passed at danger (SPAD) is an event in which a train passes a stop signal without authority, prompting automatic train protection systems to reduce the risk.
Spade
A spade is a digging tool with a flat blade and straight, sharp edge for cutting soil and roots, distinct from the shovel, which lifts loose material.
Spades (card game)
Spades is an American trick-taking card game invented in the 1930s, likely in the Midwest, with spades permanently trump. Four-player partnership play, nil bids, bags, and 500-point scoring distinguish it from bridge and whist.
Spadikam (സ്പടികം)
Spadikam (സ്ഫടികം), 1995 Malayalam action drama by Bhadran starring Mohanlal as Aadu Thoma and Thilakan as his father; 1995's biggest hit, remade thrice, re-released in 4K Dolby Atmos in 2023.
Spadina Avenue
Spadina Avenue, a major downtown Toronto north-south avenue laid out by William Warren Baldwin in 1820 as a boulevard to his Spadina estate; later the Garment District, now Chinatown's spine with the 510 streetcar right-of-way.
Spadina Expressway
The Spadina Expressway was a proposed north–south freeway in Toronto, canceled by Ontario Premier Bill Davis in 1971 after public opposition; only the William R. Allen Road was built.
Spaetzle
Spaetzle (Spätzle, Spz, gene spz) is the Drosophila cystine-knot cytokine ligand of the Toll receptor, activated by proteolytic cleavage to C-106 for embryonic dorsal-ventral patterning and innate immunity, distinct from the German noodle dish.
Spaghett
Spaghett, slang for spaghetti, is long thin durum wheat pasta. Cooked: 221 kcal per cup, low GI (33–41), whole-wheat has 4.2 g fiber per 100 g; diet quality depends on the dish.
Spaghetti
Spaghetti, from Italian spago (string), is a long thin solid durum-wheat strand, Italy's most popular pasta at over two-thirds of consumption, documented in Sicily by 1154, with a Marco Polo origin myth debunked.
Spaghetti (song)
"SPAGHETTI" (스파게티) is a 2025 alternative pop and funk single by LE SSERAFIM featuring j-hope of BTS, title track of the group's first single album; it debuted at No. 50 on the Billboard Hot 100, a career high, with lyrics comparing the group to spaghetti stuck in one's teeth.
Spaghetti alla puttanesca
Spaghetti alla puttanesca, also aulive e chiappariell, is a Neapolitan pasta with tomato, olives, capers, anchovies, garlic, and chili; named from puttana, first named in print in 1961.
Spaghetti alle vongole
Spaghetti alle vongole, Neapolitan clam pasta in bianco or in rosso, also vongole fujute; clams opened with garlic, oil, chili, parsley; pasta finished in clam liquid; blue crab crisis threatens Italian clam supply.
Spaghetti code
Spaghetti code, also called spaghetti programming, is pejorative term for tangled source code that is difficult to understand and modify, originally tied to overuse of goto.
Spaghetti junction
Spaghetti Junction is the popular name for the Gravelly Hill Interchange, the five-level junction where the M6 meets the A38(M) in Birmingham, England, opened in 1972.
Spaghetti racquet
The spaghetti racquet was a double-strung tennis racket invented by Werner Fischer around 1971 that imparted nearly twice the spin and was banned by the ITF in 1977.
Spaghetti Western
Spaghetti western, or western all'italiana: Italian-made Western film genre born in the early 1960s, initiated by Sergio Leone with A Fistful of Dollars (1964), marked by low budgets, cynical antiheroes, operatic violence, and Morricone scores.
Spaghetti-tree hoax
The spaghetti-tree hoax was a 3-minute BBC Panorama spoof broadcast 1 April 1957, showing a family in Ticino, Switzerland harvesting spaghetti from trees; narrated by Richard Dimbleby, it fooled viewers who called asking how to grow spaghetti trees.
Spaghettification
Spaghettification, also called the noodle effect, is the stretching and compression of an object by tidal forces near a black hole, drawing it into a thin strand.
Spahbed
Spahbed (اسپهبد) was a Sasanian military title meaning army chief, best known for Khosrow I's reform replacing a single army command with four regional spahbeds, one per kust.
Spahi
Spahi (Turkish sipahi, Persian for horseman): Ottoman regular cavalryman from Murad I's 14th-century corps, later indigenous cavalry of the French Armée d'Afrique, 1830s–1962, dissolved except the 1er Spahis at Valence.
Spahn Ranch
Spahn Ranch (Spahn Movie Ranch), a 55-acre Western film location in Los Angeles County near Chatsworth, California, owned by George Spahn; used for The Outlaw, Bonanza, and The Lone Ranger, and the 1968–1969 headquarters of Charles Manson's Family before a 1970 fire destroyed it.
Spain
Spain (España), Kingdom of Spain: parliamentary monarchy in southwestern Europe under the 1978 Constitution, EU member since 1986, 17 autonomous communities, population about 49.5 million, GDP growth 3.5% in 2024.
Spain AESA UAS regulation
Spain's regulation of civil drones is administered by the state aviation safety agency AESA, resting since 31 December 2020 on EU Regulations 2019/945 and 2019/947, supplemented by national decree 517/2024.
Spain during World War II
Francoist Spain in World War II: neutral in 1939, non-belligerent in 1940, neutral again in October 1943; pro-Axis sympathies, Blue Division volunteers, wolfram exports to Germany, Allied economic pressure, and postwar UN exclusion.