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Spinosauridae
Spinosauridae: family of sail-backed, fish-eating theropod dinosaurs with narrow crocodilian snouts, first named via Spinosaurus (Stromer, 1915); semiaquatic wading piscivores of Europe, Africa, South America, and Asia.
Spinosaurus
Spinosaurus (S. aegyptiacus) is a giant sail-backed, fish-eating theropod dinosaur from Late Cretaceous North Africa, named by Stromer in 1915; the longest known carnivorous dinosaur, at the center of a semiaquatic-lifestyle debate.
Spinosaurus mirabilis
Spinosaurus mirabilis, second named Spinosaurus species, described in Science in February 2026 from Niger; scimitar-shaped head crest up to 0.5 m tall, fish-eating, lived about 95 million years ago in inland Saharan rivers.
Spinothalamic tract
The spinothalamic tract, or spinal lemniscus, is a nerve fiber bundle that conveys sensations of pain, temperature, and crude touch from the spinal cord to the thalamus.
Spinous cell
Spinous cells (prickle cells) are keratinocytes of the stratum spinosum, the epidermal layer above the basal layer; named for desmosomal spines, they express K1/K10 and become granular cells.
SpinQ Technology (量旋科技)
SpinQ Technology, also known as 量旋科技, is a Chinese quantum computing company founded in 2018 in Shenzhen, developing superconducting quantum computers and desktop NMR devices.
Spinrilla
Spinrilla was an American mixtape streaming service for hip-hop, launched in 2013 by Jeffery Dylan Copeland and shut down in 2023 after a $50 million judgment.
Spinster
Spinster: originally a 14th-century occupational term for a woman who spins yarn, later the legal title for an unmarried woman in English records until the 20th century, now pejorative but reclaimed by contemporary textile artists.
SPINT1
SPINT1 (serine peptidase inhibitor, Kunitz type 1; HAI-1) is a human chromosome 15 gene encoding a membrane-bound Kunitz-type epithelial protease inhibitor that suppresses matriptase, chaperones its trafficking, and is essential for placental, skin, and intestinal integrity.
Spintronic artificial neurons
Spintronic artificial neurons are nanoscale magnetic devices, typically magnetic tunnel junctions, that reproduce the integrating and spiking behavior of biological neurons for low-power neuromorphic computing.
Spintronics
Spintronics, or spin transport electronics, is a branch of electronics that uses electron spin as well as charge, enabling devices like GMR hard disk read heads and MRAM.
Spinulosida
Spinulosida (Perrier, 1884) is an order of sea stars in class Asteroidea, superorder Spinulosacea, now restricted to the family Echinasteridae with genera Echinaster and Henricia, defined by reticulated spiny body plates.
Spinus
Spinus is a genus of finch family birds holding the American siskins and goldfinches plus the Eurasian siskin and Tibetan serin, comprising 20 species, many moved from Carduelis.
Spiny dogfish
Spiny dogfish (Squalus acanthias), also spurdog or piked dogfish: small venom-spined cold-temperate shark with 18–24 month gestation, IUCN Vulnerable; North Pacific form is the separate species S. suckleyi.
Spiny lobster
Spiny lobsters (family Palinuridae, rock lobsters) are clawless decapod crustaceans with spiny bodies and long antennae, a months-long phyllosoma larva, a puerulus postlarva, and major tropical fisheries such as the Caribbean spiny lobster Panulirus argus.
Spion Kop (stadiums)
A Spion Kop, or Kop, is a large single-tier terrace or stand at a sports stadium, named after a hill where British soldiers died in the 1900 Boer War.
Spiperone
Spiperone, also known as spiroperidol, is a butyrophenone dopamine antagonist developed by Janssen Pharmaceuticals as an antipsychotic, and a standard radioligand for labeling dopamine D2 receptors.
Spira Spica
Spira Spica (スピラ・スピカ) is a Japanese pop-rock project from the Kansai region, fronted by vocalist Mikiha and known for the My Dress-Up Darling opening theme Sansan Days.
Spiraea
Spiraea (spirea, bridal-wreaths), a Rosaceae shrub genus published by Linnaeus in 1753, native to the temperate Northern Hemisphere with about 100 accepted species, most diverse in eastern Asia; Japanese spiraea is invasive in the US.
Spiral
A spiral, in mathematics, is a curve whose radius changes as it revolves about a fixed point, winding ever outward or inward; Archimedes studied it about 225 BC.
Spiral (2021 film)
Spiral: From the Book of Saw (2021) is the ninth Saw film, directed by Darren Lynn Bousman from Chris Rock's idea, starring Rock, Samuel L. Jackson, and Max Minghella as police hunt a Jigsaw-style killer targeting corrupt cops; released May 14, 2021, it earned 39% on Rotten Tomatoes.
Spiral (TV series)
Spiral (Engrenages) is a French police and legal drama, Canal+'s first internationally successful crime series, running eight seasons (2005–2020, 86 episodes) about Paris's 2e DPJ unit, with Laure Berthaud, Joséphine Karlsson, and Judge Roban; International Emmy 2015.
Spiral antenna
A spiral antenna is a wideband, frequency-independent antenna with conductive arms wound in a spiral, radiating circularly polarized waves; it is used in direction finding, electronic warfare, and GPS.
Spiral arm
A spiral arm is a region of denser gas, dust, and young stars winding outward from the center of a disk galaxy, giving spiral galaxies their pinwheel appearance.
Spiral bevel gear
A spiral bevel gear is a bevel gear with curved, oblique teeth that transmit power between intersecting shafts, most often at 90 degrees, more smoothly than straight bevel gears.
Spiral Cone-Beam Computed Tomography
Spiral cone-beam computed tomography, also called helical cone-beam CT, unites a cone-shaped x-ray beam with continuous spiral gantry rotation and table movement, first published in 1991.
Spiral CT
Spiral CT, also called helical CT, is a CT mode in which the tube rotates continuously while the table moves, scanning a whole volume in 20 to 60 seconds.
Spiral enteroscopy
Spiral enteroscopy is a device-assisted deep enteroscopy technique in which a rotating spiral-tipped overtube pleats the small intestine over the enteroscope, allowing diagnosis and treatment of small-bowel disease.
Spiral galaxy
A spiral galaxy is a galaxy with a rotating disk of stars, gas, and dust arranged in spiral arms around a central bulge, like the Milky Way.
Spiral ganglion
The spiral ganglion is a group of sensory neurons in the cochlea of the inner ear that relays sound information from hair cells to the brainstem.