All articles starting with O
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Orchids of subantarctic and oceanic islands
The orchids of subantarctic and oceanic islands are the exceptionally sparse orchid floras of remote islands, with Macquarie Island at 55°S marking the family's southernmost limit.
Orchids of the Caribbean
The orchids of the Caribbean are the roughly 600 to 728 orchid species native to the West Indies, where 42 to 72 percent of species grow nowhere else.
Orchids of the Pacific Islands
The orchids of the Pacific Islands are the orchid floras of Melanesia, Micronesia, and Polynesia in Oceania, where a survey of 63 islands found 552 species in 110 genera.
Orchiectomy
Orchiectomy, also spelled orchidectomy, is surgery to remove one or both testicles. It treats testicular and prostate cancer, removes damaged testicles, and serves as a gender-affirming procedure.
Orchiopexy
Orchiopexy (orchidopexy) is surgery that moves an undescended testis into the scrotum, the standard treatment for cryptorchidism, recommended between 6 and 18 months of age; also fixes the testis after torsion. First successful operation by Thomas Annandale, 1877.
Orchis
Orchis (Tourn. ex L., 1753) is a genus of about 20 terrestrial Eurasian orchids in Orchidaceae, subtribe Orchidinae, type species O. militaris; formerly broader, now excluding Anacamptis and Neotinea, growing on calcareous soils.
Orchitis or epididymitis
Orchitis or epididymitis (epididymo-orchitis) is inflammation of the testis, epididymis, or both, usually from STIs in younger men, enteric bacteria in older men, or mumps virus; treated with ceftriaxone, doxycycline, or fluoroquinolones.
Orchomenos (Arcadia)
Orchomenos (Erchomenos, Arcadian Orchomenos) was an ancient city of northeastern Arcadia on a hill near Levidi, seat of Arcadia's kings, named in Homer's ship catalogue, with a 3rd-century-BC theatre of 4,000 seats, excavated since 1913.
Orchomenos/Orchomenus (Boeotia)
Orchomenos (Ὀρχομενός, Orchomenus) was an ancient city in NW Boeotia, Greece, at Lake Copais; a leading Mycenaean center famed for the Treasury of Minyas, Minyan ware, and the Kopais drainage, later a Boiotian League city.
ORCID
ORCID (Open Researcher and Contributor ID) is a US-based non-profit providing free 16-digit identifiers that researchers control, linking their publications, affiliations, and funding since the registry launched in 2012.
Orcus
Orcus: Latin name for the Roman underworld and its god, probably of Etruscan origin, later equated with Pluto and Dis Pater; no cult, source of Italian orco and French ogre, and namesake of dwarf planet 90482 Orcus.
Orcus Patera
Orcus Patera is a 387.64 km elongated patera on Mars at 14.13 N, 178.35 E near Elysium Planitia, an IAU-approved 1973 classical albedo name whose origin, oblique impact crater or volcanic caldera, remains debated.
Ord och Bild
Ord och Bild is a Swedish illustrated cultural journal founded in 1892 by critic Karl Wåhlin, the oldest in Sweden, known for radical liberal and left-wing phases.
Ord River Floodplain
The Ord River Floodplain is a Ramsar wetland of international importance covering 140,766 hectares at the Ord River's mouth near Wyndham in the Kimberley, Western Australia, listed in 1990.
Orde Wingate
Orde Charles Wingate (1903–1944), British major general and DSO with two bars, founded the Special Night Squads in Palestine, led Gideon Force in Ethiopia, and commanded the Chindits in Burma, dying in a B-25 crash on 24 March 1944.
Ordeal by Innocence
Ordeal by Innocence is a 1958 Agatha Christie mystery novel in which Dr Arthur Calgary arrives too late with proof that a convicted murderer was innocent.
Ordeal by Innocence (TV series)
Ordeal by Innocence (2018) is Sarah Phelps's three-part BBC One adaptation of Agatha Christie's 1958 novel, starring Bill Nighy and Anna Chancellor, set at Christmas 1954 in Scotland, notable for Ed Westwick's recasting with Christian Cooke and a changed killer.
Ordeal of the bitter water
The ordeal of the bitter water, or sotah, is a biblical trial in Numbers 5:11–31 in which a wife suspected of adultery drinks cursed water.
Orden Ogan
Orden Ogan is a German power metal band from Arnsberg in North Rhine-Westphalia, led by Sebastian "Seeb" Levermann, with seven studio albums and two consecutive Top 3 German chart entries.
Ordenanças
The Ordenanças were a hierarchical militia system of Portugal and its colonies, created by law in 1549, in which captains-mor mustered all able-bodied men for defense and internal order.
Ordenanzas de 1518 (Cortés expedition authorization)
The Ordenanzas de 1518 were the written instruments by which Diego Velázquez, governor of Cuba, authorized Hernán Cortés in October 1518 to lead a fleet to Yucatán.
Ordenanzas de 1524 (Council creation cédula)
The Ordenanzas de 1524 is the cédula of 1 August 1524 by which Carlos I of Spain created the Real y Supremo Consejo de Indias.
Ordenanzas de 1574 (Toledo's mita cédula)
The Ordenanzas de 1574 were issued by Viceroy Francisco de Toledo of Peru to organize the Potosí mita, a forced Indigenous labor draft for the mines.
Ordenanzas de descubrimiento, nueva población y pacificación de las Indias (1573)
The Ordenanzas de descubrimiento, nueva población y pacificación de las Indias were royal ordinances issued by Philip II of Spain in 1573, replacing conquest with peaceful settlement.
Ordenanzas de Intendentes (1782)
The Ordenanzas de Intendentes de 1782 was a royal ordinance of Charles III establishing the intendant system in the Viceroyalty of the Río de la Plata.
Ordenanzas de Minería de Nueva España
The Ordenanzas de Minería de Nueva España is the mining code of New Spain, approved by Charles III in 1783 and drafted by Joaquín Velázquez de León.
Ordenanzas of Viceroy Francisco de Toledo
The Ordenanzas of Viceroy Francisco de Toledo were ordinances issued in Peru between 1569 and 1581, reorganizing colonial rule through reducciones, tribute, and the mita.
Order (biology)
Order (ordo) is a Linnaean taxonomic rank between class and family, introduced by Linnaeus in 1735; exemplified by Carnivora, applied across animals, plants, fungi, prokaryotes, and viruses (105 ICTV orders).
Order (ring theory)
In ring theory, an order is a subring of the ring of integers of a number field that has finite index there, a concept introduced by Richard Dedekind.
Order analysis
Order analysis is a signal processing method that extracts harmonic components, or orders, from vibration measurements of rotating machinery as a function of rotational speed rather than time.