All articles starting with O
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Order of the Golden Fleece
Order of the Golden Fleece (Toison d'Or, Goldenen Vlies, Toisón de Oro): Catholic order of chivalry founded 10 January 1429/30 at Bruges by Philip the Good, Duke of Burgundy; since 1700 split into Spanish branch under Felipe VI and Austrian branch under Karl von Habsburg.
Order of the Indian Empire
The Most Eminent Order of the Indian Empire, a British order of chivalry founded by Queen Victoria on 1 January 1878 with grades GCIE, KCIE, and CIE, rewarded service in British India and ceased being awarded in 1947.
Order of the New Templars
Order of the New Templars (Ordo Novi Templi, ONT, Neutempler-Orden): occult-Ariosophic order founded around 1900 by Lanz von Liebenfels, promoting Aryan racial ideology under Templar symbolism; banned by the Nazis.
Order of the Phoenix (fictional organisation)
Order of the Phoenix: fictional secret society in J.K. Rowling's Harry Potter, founded by Dumbledore against Voldemort and the Death Eaters; formed in the 1970s, reformed 1995, based at 12 Grimmauld Place, distinct from Dumbledore's Army.
Order of the Red Banner (Орден Красного Знамени)
Order of the Red Banner (Орден Красного Знамени), the first Soviet military order, established September 16, 1918 for combat heroism, highest USSR military order until 1930, discontinued 1991.
Order of the Red Banner of Labour (Орден Трудового Красного Знамени)
Order of the Red Banner of Labour (Орден Трудового Красного Знамени), Soviet civilian labor order, RSFSR order from 28 December 1920, all-Union from 7 September 1928, over 1.2 million awards, last given 1991.
Order of the Rising Sun (旭日章)
The Order of the Rising Sun (旭日章) is Japan's first national decoration, founded April 10, 1875, awarded for meritorious service to the state and for contributions to Japan's international relations, with six classes since 2003 reforms.
Order of the Sinking Star
Order of the Sinking Star (沉星之序) is a 2026 puzzle adventure by Thekla, Inc., directed by Jonathan Blow, published by Arc Games for PC, Switch 2, and PS5 at $29.99, with 1,000+ hand-crafted puzzles in a four-world Sokoban 'supercollider' design.
Order of the Solar Temple
The Order of the Solar Temple (Ordre du Temple Solaire) was a neo-Templar new religious movement founded in 1984, known for the mass deaths of 74 members between 1994 and 1997.
Order of the Star of India
Order of the Star of India (Most Exalted Order of the Star of India): British order of chivalry founded 1861 for service in India, with GCSI, KCSI, CSI ranks; Viceroy as Grand Master; last appointments June 1947.
Order of the Star of Romania
Order of the Star of Romania (Ordinul Steaua României), Romania's highest national order of merit, founded 10 May 1877 by Prince Carol I, abolished 1947, reinstituted 1998, with six grades awarded by the President.
Order of the Thistle
The Most Ancient and Most Noble Order of the Thistle is Scotland's highest order of chivalry, founded in its modern form by James VII in 1687, with 16 Knights and Ladies, motto Nemo me impune lacessit, chapel at St Giles' Cathedral, Edinburgh.
Order of the White Eagle (Poland)
Order of the White Eagle (Order Orła Białego), Poland's highest state decoration, founded 1 November 1705 by Augustus II, restored 1921 and 1992; civil and military merit; revoked from Zelenskyy in 2026.
Order parameter
An order parameter is a thermodynamic quantity distinguishing phases, zero in the disordered phase and nonzero in the ordered one, introduced by Lev Landau in 1937.
Order statistic
An order statistic is one of a statistical sample's values arranged in increasing order; the first is the sample minimum and the last is the sample maximum.
Order statistics
Order statistics are the values of a random sample arranged in increasing order, with the jth smallest called the jth order statistic; the theory underlies the sample median, quantiles, trimmed means, and extremes.
Order theory
Order theory is the branch of mathematics that studies partially ordered sets, or posets, together with structures built on them such as lattices and ordered algebraic systems.
Order to Expel the Barbarians
The Order to Expel the Barbarians was an 1863 imperial decree ordering foreigners out of Japan; the Chōshū domain carried it out by firing on ships at Shimonoseki.
Order to Provide Fuel and Water
The Order to Provide Fuel and Water (薪水給与令) was an 1842 edict of the Edo shogunate reversing the 1825 order to drive foreign ships away by force.
Order Up
Order Up is a 2025 American animated SpongeBob SquarePants short directed by Sean Charmatz, in which SpongeBob's joy of ringing the Krusty Krab's order-up bell infuriates Squidward.
Order-n formulation
The Order-n formulation is a recursive method for computing the dynamics of articulated multibody systems whose computational cost grows linearly with the degrees of freedom, using algorithms introduced by Roy Featherstone.
Order–disorder transition
An order–disorder transition is a transition in which the degree of order of a system changes; in alloys, atoms occupy preferred sublattices below a critical temperature.
Ordered abelian groups
An ordered abelian group is an abelian group with a total order compatible with addition, such as the integers, rationals, and reals; it is central to model theory.
Ordered logit
Ordered logit, also known as the proportional odds model, is a statistical regression method for ordinal outcomes with ordered categories, formulated by Peter McCullagh in 1980.
Ordered pair
An ordered pair (a, b) is a mathematical object with a first and second coordinate, so (a, b) equals (c, d) only when a = c and b = d.
Ordered probit model
The ordered probit model is a regression method for ordinal dependent variables, proposed by Aitchison and Silvey in 1957 and estimated by maximum likelihood, assuming normally distributed errors.
Ordered statistics CFAR
Ordered statistics CFAR (OS-CFAR) is a radar detection scheme proposed by Hermann Rohling in 1983 that estimates background noise by sorting reference cells, tolerating multiple interfering targets.
Ordericus Vitalis
Ordericus Vitalis (1075–c. 1142) was an English-born Benedictine monk of the Norman abbey of Saint-Évroul, author of the thirteen-book Historia Ecclesiastica, a key source for Anglo-Norman history.
Ordermark
Ordermark was a Los Angeles software company, founded in 2017, that aggregated orders from delivery services like Uber Eats and DoorDash into one dashboard for restaurants; UrbanPiper bought its U.S. business in 2023.
Orders of magnitude (length)
Orders of magnitude (length) are the powers of ten spanning the measurable range of distances, from the Planck length at 10⁻³⁵ m to the observable universe.