All articles starting with S
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Standard Industrial Classification
The Standard Industrial Classification, known as SIC codes, is a US system of four-digit industry codes developed in the 1930s, largely replaced by NAICS in 1997.
Standard instrument departure
A standard instrument departure (SID) is a preplanned IFR departure route, published in graphic form, linking a runway with the en route structure; it requires ATC clearance.
Standard Insurance Company
Standard Insurance Company, marketed as The Standard, is a Portland, Oregon-based insurer selling group disability, group life, and retirement benefits, owned by Japan's Meiji Yasuda since 2016.
Standard language
A standard language, also called a standard dialect or standardized language, is the variety treated as the norm for writing, education, media, and formal public life.
Standard Liège
Standard Liège, known as Royal Standard de Liège, is a Belgian professional football club founded in Liège in 1898 that has won 10 Belgian championships and 8 Belgian Cups.
Standard linear solid model
The standard linear solid model, also called the Zener model, is a three-element viscoelastic model introduced by Clarence Zener in 1948 to describe anelastic behavior in metals.
Standard Method of Measurement
The Standard Method of Measurement (SMM) is a British set of rules for measuring building work in bills of quantities, first issued in 1922 by the Royal Institution of Chartered Surveyors.
Standard Missile
The Standard Missile is a family of ship-launched guided missiles that serves as the United States Navy's primary air-defense weapon, fielded aboard Aegis cruisers and destroyers since the late 1960s.
Standard ML
Standard ML (SML) is a strictly evaluated functional programming language with type inference and a formal specification, The Definition of Standard ML, first published in 1990.
Standard Model
The Standard Model, also called the standard model of particle physics, is the quantum field theory describing elementary particles and three of the four fundamental forces, excluding gravity.
Standard Model effective field theory
Standard Model effective field theory (SMEFT) extends the Standard Model Lagrangian with higher-dimensional, gauge-invariant operators that capture how undiscovered heavy particles would deform its predictions.
Standard molar entropy
Standard molar entropy, symbol S°, is the entropy of one mole of a substance in its standard state, in J/(mol·K), tabulated at 298.15 K; unlike enthalpy, values are absolute entropies.
Standard motorcycle
A standard motorcycle, often called a naked bike or roadster, is a road motorcycle with an upright riding position, waist-height handlebars, and little or no fairing.
Standard normal table
The standard normal table, commonly called the z-table, lists areas under the standard normal curve for z-scores, letting one table serve normal distributions of any mean and standard deviation.
Standard normal variate
Standard normal variate (SNV) is a row-wise normalization method for spectroscopic data, devised by Barnes, Dhanoa, and Lister in 1989 to correct multiplicative scatter in near-infrared diffuse reflectance spectra.
Standard Nuclear, Inc.
Standard Nuclear, Inc. is an Oak Ridge, Tennessee-based manufacturer of TRISO advanced nuclear fuel, founded in 2024 and listed on the NYSE under STDN since July 2026.
Standard Occupational Classification
The Standard Occupational Classification (SOC) is the United States federal system for classifying workers into occupational categories, directed by the Office of Management and Budget since the 1970s.
Standard of care
Standard of care: the legal benchmark of reasonable conduct in negligence, from the objective reasonable person test (Vaughan v Menlove, 1837) to professional medical standards (Bolam, Montgomery) and the ALI's 2024 Restatement revision.
Standard of deferred payment
The standard of deferred payment is the thing of value in which a debt is expressed and later discharged, usually money, and is listed as a fourth function of money.
Standard of living
Standard of living, or living standards, is the material well-being a household derives from its income, usually measured as disposable income divided by consumption units reflecting household needs.
Standard of Ur
The Standard of Ur, or Royal Standard of Ur, is a mosaic-inlaid wooden box excavated by Leonard Woolley at Ur in the 1920s, now in the British Museum.
Standard Oil
Standard Oil was an American oil refining and pipeline enterprise founded by John D. Rockefeller, which controlled most US petroleum refining until the Supreme Court dissolved it in 1911.
Standard Oil of Ohio (Sohio)
Standard Oil of Ohio, known as Sohio, was an American petroleum company in Cleveland, BP's principal United States arm from 1969 until the brand retired in 1991.
Standard operating procedure
A standard operating procedure (SOP), also called a standing operating procedure, is a written step-by-step document ensuring tasks are performed consistently, accurately, and with quality.
Standard penetration test
The standard penetration test (SPT) is a widely used in-situ geotechnical test that records the hammer blows needed to drive a sampler into soil, giving the N-value.
Standard precautions
Standard precautions are the minimum infection prevention practices applied to every patient in every healthcare setting, regardless of infection status, set out by the CDC in 1996.
Standard probability space
A standard probability space, also known as a Lebesgue-Rokhlin space, is the completion of a standard Borel space with a probability measure, a setting where regular conditional probabilities exist.
Standard quantum limit
The standard quantum limit (SQL), or shot-noise limit, is the precision of an ideal measurement with uncorrelated quantum particles, scaling as N to the −1/2; squeezed light and entanglement can beat it.
Standard RAID levels
The standard RAID levels are numbered configurations, RAID 0 through RAID 6, that combine disk drives into arrays, each trading off performance, capacity, and drive-failure tolerance. They were classified at UC Berkeley in 1988.
Standard Schnauzer
Standard Schnauzer: original medium-sized German Schnauzer breed, 35–45 lb, black or pepper-and-salt wiry coat; formerly Wire-haired Pinscher, AKC-recognized 1904, Working Group since 1937.