All articles starting with O
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October Revolution (Октябрьская революция)
October Revolution (Октябрьская революция), also called the Bolshevik Revolution or Great October Socialist Revolution: the Bolshevik armed seizure of power in Petrograd, October 24–25, 1917 (Julian), overthrowing the Provisional Government, issuing the Decrees on Peace and Land, and founding the first communist state.
October Revolution Island
October Revolution Island (Ostrov Oktyabrskoy Revolyutsii), largest island of Severnaya Zemlya, Krasnoyarsk Krai, Russia; 14,200 km², 965 m Mount Karpinsky, over half glaciated, charted 1930–32 by Ushakov and Urvantsev.
October Sky
October Sky (1999), Joe Johnston drama starring Jake Gyllenhaal, Chris Cooper, and Laura Dern, adapted from Homer Hickam's memoir Rocket Boys, an anagram of the title, about a Coalwood, West Virginia teen inspired by Sputnik to build rockets.
October surprise
October surprise: a late-breaking news event or crisis in the final weeks of a US election campaign, coined by William Casey during Reagan's 1980 race; famous cases include 1880, 1968, 2000, 2016.
October: Ten Days That Shook the World (Октябрь)
October (Октябрь, Oktyabr), also Ten Days That Shook the World, is Eisenstein and Aleksandrov's 1927 Sovkino silent film on the 1917 Bolshevik revolution, commissioned for its tenth anniversary, censored for Trotsky scenes, and famed for intellectual montage.
Octochaetus multiporus
Octochaetus multiporus (Milkworm, Maori worm) is a New Zealand native anecic earthworm up to 30 cm long, burrowing 3–5 m deep, that squirts glowing orange-yellow coelomic fluid when disturbed and was used by Māori as eel fishing bait.
Octocog alfa
Octocog alfa is recombinant full-length human coagulation factor VIII for haemophilia A, sold as Advate (Takeda, 2003) and Kovaltry (Bayer); intravenous replacement therapy, prophylaxis, and surgery, not for von Willebrand disease.
Octocoral genera
Octocoral genera are formally named groups of species within Octocorallia, the soft corals, gorgonians, and sea pens with eight-tentacled polyps, reclassified into two orders in a 2022 revision.
Octocorallia
Octocorallia (octocorals): anthozoan class of about 3500 marine species, soft corals, gorgonians, sea pens, blue corals, defined by eight pinnate tentacles and eight mesenteries; revised 2022 into orders Scleralcyonacea and Malacalcyonacea.
Octodon
Octodon, the degus, is a South American genus of octodontid rodents erected by Bennett in 1832; five species are recognized, including the diurnal, social Chilean lab animal Octodon degus.
Octol
Octol is a melt-cast military high explosive of HMX and TNT, developed in 1952 and used where more power than Composition B is needed, such as shaped-charge warheads.
OctoMap
OctoMap is an open-source C++ framework for probabilistic 3D occupancy mapping based on octrees, developed at the University of Freiburg and used for collision checking and path planning on robots.
Octomedusa
Octomedusa (Octomedusa pieckorum) is a fossil jellyfish genus from the Pennsylvanian Mazon Creek deposits of Illinois, preserved in siderite concretions and classed as a Paleozoic coronate, later treated as hydrozoan or scyphozoan.
Octomom Home Alone
Octomom Home Alone is a 2012 adult video starring Nadya Suleman (Octomom) as herself, directed by Brad Armstrong for Wicked Pictures; title revealed on TMZ Live, online release June 20, DVD to follow.
Octon
Octon: a Yorkshire settlement in Thwing parish recorded in the 1086 Domesday Book (held by King William, formerly Grimkel, 3 hides), and separately an ancient sanctuary site in Gaul catalogued as BAtlas 15 A2.
Octonauts
Octonauts is a preschool animated franchise created by Meomi (Vicki Wong and Michael C. Murphy), beginning with 2006 books and premiering on CBeebies October 4, 2010; produced by Brown Bag Films for Chorion and Silvergate Media, it follows Captain Barnacles' eight-animal crew rescuing sea creatures from the Octopod, with the Above & Beyond land spin-off.
Octonion
Octonions, also known as Cayley numbers, form an 8-dimensional normed division algebra over the real numbers, described by John Graves in 1843 and published by Arthur Cayley in 1845.
Octonions
The octonions, also known as Cayley numbers or octaves, are an eight-dimensional number system whose multiplication is neither commutative nor associative, the largest of the four normed division algebras.
Octopamine
Octopamine is a biogenic amine, first found in octopus salivary glands in 1948, that serves as a neurotransmitter and neurohormone in invertebrates, regulates insect behavior, and occurs as a trace amine in mammals.
Octopamine receptor
Octopamine receptors are invertebrate G protein-coupled receptors for the tyramine-derived amine octopamine, signaling via cAMP and Ca2+. Insect α- and β-adrenergic-like subtypes (OAMB, OctβR) are key insecticide targets, notably amitraz.
Octopath Traveler
Octopath Traveler (オクトパストラベラー) is Square Enix and Acquire's 2018 Nintendo Switch HD-2D JRPG: eight travelers with separate stories on Orsterra, Break and Boost turn-based combat, Path Actions, and a job system.
Octopath Traveler 0
Octopath Traveler 0 (オクトパストラベラー0) is Square Enix's 2025 HD-2D JRPG prequel for Switch, PS, Xbox, and PC, reimagining the mobile game Champions of the Continent with 8-member battles and Wishvale town rebuilding.
Octopus
Octopus (Cuvier, 1797) is a genus of benthic octopodid cephalopods with type species Octopus vulgaris; about 200 species, ink sac, two-row suckers, and a cryptic vulgaris species complex.
Octopus (software)
Octopus is a free, open-source scientific code, first described in 2006, that uses time-dependent density-functional theory to simulate electron and ion dynamics in finite systems responding to electromagnetic fields.
Octopus (yacht)
Octopus is a 126-meter explorer motor yacht built by Lürssen in 2003 for Microsoft co-founder Paul Allen, later used in the discovery of the battleship Musashi.
Octopus as food
Octopus as food is the human consumption of octopuses, chiefly the common octopus, supplied almost entirely by wild fisheries, with global production about 370,000 tons.
Octopus Group (financial services)
Octopus Group is a privately held London-based family of financial-services, energy, and education businesses, founded in 2000 by Simon Rogerson, Chris Hulatt, and Guy Myles, who remain its largest shareholders.
Octopus Power
Octopus Power (章鱼动力) is a Beijing-based embodied-intelligence startup founded in January 2026 by Du Dalong, which raised nearly RMB 1 billion in its first four months.
Octopus sensu stricto
Octopus vulgaris sensu stricto, the common octopus (Cuvier 1797), is the Mediterranean and northeastern Atlantic species, distinguished from the Octopus vulgaris species complex of at least six cryptic relatives including O. sinensis, O. americanus, and O. tetricus.
Octopus wrestling
Octopus wrestling: extinct 1950s-1960s spectator sport of Puget Sound, Washington, where divers dragged giant Pacific octopuses from dens to the surface; World Octopus Wrestling Championship drew thousands before Washington banned it in 1976.