All articles starting with O
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Orowan strengthening
Orowan strengthening is a precipitation and dispersion hardening mechanism, described by Egon Orowan in 1948, in which dislocations bow between non-shearable particles and bypass them, leaving loops that raise the alloy's strength.
Orphan
Orphan: a child under 18 who has lost one parent (single orphan) or both parents (double orphan). Covers UNICEF definitions, AIDS-related orphanhood, the history of orphanages, and research comparing institutional and family-based care.
Orphan (2009 film)
Orphan is a 2009 American psychological horror film directed by Jaume Collet-Serra, in which a grieving couple adopts a nine-year-old girl named Esther who proves dangerously disturbed.
Orphan (2025 film)
Orphan (Árva) is László Nemes's 2025 Hungarian historical drama, set in 1957 Budapest, about Jewish boy Andor confronting a man claiming to be his father; Venice 2025 competition, Hungary's 2026 Oscar entry.
Orphan (film series)
Orphan film series: American psychological horror franchise starring Isabelle Fuhrman as Esther/Leena Klammer, comprising Orphan (2009), the prequel Orphan: First Kill (2022), and a third film in production.
Orphan Black
Orphan Black: Canadian sci-fi thriller created by Graeme Manson and John Fawcett, aired 2013-2017 on Space and BBC America, five seasons, 50 episodes. Tatiana Maslany played 17 clones of Sarah Manning; won 2016 Emmy and a Peabody; spin-off Echoes (2024).
Orphan drug
Orphan drug: a medicine for a rare disease supported by regulatory incentives. US Orphan Drug Act 1983 (fewer than 200,000 patients, 7-year exclusivity, 50% tax credit); EU regulation 2000 (5 in 10,000, 10-year exclusivity, COMP).
Orphan Nuclear Receptor
Orphan nuclear receptors (ONRs) are nuclear receptor transcription factors identified without known endogenous ligands; 24 of 48 human NRs were once orphans, with ligands such as lipids, heme, and phospholipids since found for ROR, REV-ERB, and others.
Orphan Train
The Orphan Train Movement relocated roughly 150,000 to 250,000 poor New York children to rural families in the Midwest and West between 1854 and 1929, pioneering American foster care.
Orphan: First Kill
Orphan: First Kill (2022), also known as a prequel to Orphan (2009), is a Paramount+ psychological horror film directed by William Brent Bell in which Isabelle Fuhrman reprises Esther, escaped Estonian patient Leena Klammer impersonating a dead Connecticut girl, with a mother's-cover-up twist.
Orphanage
Orphanage, also called residential or institutional care, is a facility where children separated from parents live under paid staff. About 2 million children live in such care worldwide, most with living relatives; institutionalization harms development, driving deinstitutionalization toward kinship and foster care.
Orphans (1998 film)
Orphans (1998) is Peter Mullan's debut feature, a Glasgow-set black comedy-drama about four siblings scattered through a stormy night before their mother's funeral; it won Best Film at Venice Critics' Week 1998.
Orphans (upcoming film)
Orphans (also known as Orphan 3) is an upcoming American horror thriller, the third Orphan franchise film, directed by William Brent Bell, written by David Coggeshall, starring Isabelle Fuhrman as Esther; filmed in Budapest, scheduled April 30, 2027.
Orphans of the Storm
Orphans of the Storm (1921) is D.W. Griffith's silent epic starring Lillian and Dorothy Gish as sisters in the French Revolution, adapted from Les Deux Orphelines, his last film with Lillian Gish.
Orphenadrine
Orphenadrine, sold as Norflex and usually given as the citrate salt, is a skeletal muscle relaxant and mild analgesic used for painful musculoskeletal conditions and Parkinson's disease.
Orpheu
Orpheu was a Portuguese literary magazine launched in Lisbon in 1915, whose two issues assembled the poets around Fernando Pessoa and began modernism in Portugal.
Orpheu generation
The Orpheu generation (Geração de Orpheu) was the group of young Portuguese poets, led by Fernando Pessoa and Mário de Sá-Carneiro, whose 1915 magazine Orpheu began Portuguese modernism.
Orpheus (Ὀρφεύς)
Orpheus is a mythical Greek singer whose music moves nature and reaches the dead. Stories about Eurydice, the Argonauts, and sacred knowledge shaped his literary and religious significance.
Orpheus and Eurydice
Orpheus and Eurydice (Εὐρυδίκη), the Greek myth of the musician Orpheus descending to the Underworld to recover his wife and losing her by looking back; known chiefly through Virgil's Georgics and Ovid's Metamorphoses and foundational to opera from Peri's Euridice (1600) onward.
Orpheus Descending
Orpheus Descending is Tennessee Williams's 1957 Broadway drama, a revision of Battle of Angels recasting the Orpheus and Eurydice myth as wandering guitarist Val Xavier and Lady Torrance in a Southern town.
Orpheus in the Underworld
Orpheus in the Underworld (Orphée aux enfers) is Jacques Offenbach's satirical operetta, premiered Paris 1858, libretto by Crémieux and Halévy, famous for the can-can galop infernal and parodying the Orpheus myth and Napoleon III's Second Empire.
Orphic poetry
Orphic poetry is the body of ancient Greek hexameter verse attributed to the mythical singer Orpheus, preserved mainly in fragments, gold grave tablets, and the Derveni Papyrus.
Orphism (art)
Orphism, or Orphic Cubism, was an abstract Cubist-influenced painting style developed around 1912 in Paris by Robert and Sonia Delaunay and František Kupka; Guillaume Apollinaire coined the name after Orpheus, linking color-driven abstraction to music.
Orpiment
Orpiment, also known as King's yellow or Auripigment, is a yellow arsenic sulfide mineral found in hydrothermal veins and hot springs, long used as a golden-yellow artist's pigment until abandoned for its toxicity.
Orpington chicken
Orpington chicken: British dual-purpose chicken breed created by William Cook in Orpington, Kent, in 1886 (Black Orpington from Minorca, Plymouth Rock, Langshan crosses). Buff, Black, White, Blue APA varieties; calm, broody; large brown eggs; graduated Livestock Conservancy endangered list 2016.
Orqa
Orqa, legally ORQA d.o.o., is a Croatian technology company founded in Osijek in late 2018 that designs FPV drones and video goggles, producing up to 280,000 NDAA-compliant drones yearly.
Orquesta Akokan
Orquesta Akokán is a Cuban mambo orchestra founded by José "Pepito" Gómez, Jacob Plasse, and Michael Eckroth, whose 2018 Daptone debut earned a 2019 Grammy nomination.
Orquesta de la Luz
Orquesta de la Luz (オルケスタ・デ・ラ・ルス) is a Japanese salsa orchestra formed in Tokyo in 1984, led by vocalist Nora Suzuki, whose 1990 debut album topped Billboard's US Latin chart for 11 weeks.
Orquesta Filarmónica de Jalisco
The Orquesta Filarmónica de Jalisco, known until 1988 as the Orquesta Sinfónica de Guadalajara, is a symphony orchestra founded in 1915 in Guadalajara, Mexico, resident at the Teatro Degollado.
Orquestra Frevo das Colinas
Orquestra Frevo das Colinas is a frevo orchestra from Garanhuns, Pernambuco, Brazil, a brass-and-percussion ensemble that played regional events for a decade before its 2023 festival debut.