All articles starting with N
16,460 articles
Non-deliverable forward
A non-deliverable forward (NDF) is a foreign exchange forward contract settled with a net cash payment, typically in US dollars, used for currencies under capital controls.
Non-denominational
Non-denominational, also called transdenominational, describes Christian churches and believers with no denominational affiliation; such churches govern and fund themselves without a denominational hierarchy.
Non-denominational Muslim
A non-denominational Muslim, also called a non-sectarian Muslim, is a Muslim who affirms Islamic belief and obligations while declining to identify with either major branch, Sunni or Shia.
Non-dialable point
A non-dialable point was a telephone line that could not be reached by dialing, so calls to it were completed manually by a long distance operator.
Non-dimensionalization
Non-dimensionalization rescales the variables of a governing equation by characteristic units so that the equation, its solutions, and its parameters become dimensionless, simplifying comparison and simulation.
Non-directional beacon
A non-directional beacon (NDB) is a ground-based radio navigation transmitter, among the oldest aids still in aviation use, that lets equipped pilots determine bearings and home on it.
Non-disclosure agreement
A non-disclosure agreement (NDA), or confidentiality agreement, is a contract keeping specified information confidential. Covers trade secrets, employment and settlement uses, the US Speak Out Act, UK Employment Rights Act 2025, and research on NDAs' labor-market effects.
Non-disintegrating belt
A non-disintegrating belt is a machine-gun ammunition belt whose links remain joined after firing, so the empty belt emerges intact, unlike the disintegrating belt, whose links fall away.
Non-dominated sorting genetic algorithm
The non-dominated sorting genetic algorithm (NSGA) is a family of multi-objective evolutionary algorithms, introduced by Srinivas and Deb in 1994, that evolves a whole set of trade-off solutions in one run.
Non-English-based programming languages
Non-English-based programming languages express keywords, syntax, numerals, or error messages in natural languages other than English; they have existed since the 1960s, and studies show localized languages help novices learn faster.
Non-equilibrium plasma
Non-equilibrium plasma, also called non-thermal or cold plasma, is an ionized gas whose electrons reach about 10,000 K while the gas stays near ambient temperature.
Non-equilibrium steady state
A non-equilibrium steady state (NESS) is a state of a physical system in which macroscopic properties stop changing even as currents of energy, particles, or momentum flow through it continuously.
Non-equilibrium thermodynamics
Non-equilibrium thermodynamics is the branch of thermodynamics describing heat, mass, charge, and momentum transport and irreversible phenomena in systems not in global equilibrium, founded on Lars Onsager's 1931 reciprocal relations.
Non-erosive gastro-oesophageal reflux disease
Non-erosive gastro-esophageal reflux disease (NERD), also called nonerosive reflux disease, is the more common form of GERD, causing troublesome heartburn and regurgitation without esophageal erosions on endoscopy, treated with proton pump inhibitors.
Non-essential and conditionally essential amino acids
Non-essential amino acids are the proteinogenic amino acids the body can synthesize de novo, while conditionally essential ones, like arginine and tyrosine, become dietary requirements under specific physiological conditions.
Non-Euclidean geometry
Non-Euclidean geometry, also known as non-Euclidean space, is geometry built on alternatives to Euclid's parallel postulate, arising in the early nineteenth century from the work of Gauss, Bolyai, and Lobachevski.
Non-executive director
Non-executive director (NED): a board member outside executive management who scrutinizes and challenges the executive. Central to the 1992 Cadbury Report and the UK Corporate Governance Code's comply-or-explain regime.
Non-expected utility
Non-expected utility is the family of decision theories that modify or replace expected utility under risk, accommodating predictable departures such as the Allais paradox and prospect theory.
Non-Fermi liquid
A non-Fermi liquid, also known as a strange metal, is a metallic quantum state lacking well-defined electron quasiparticles due to strong quantum fluctuations, first observed experimentally in 1991 and since found in cuprates and heavy-fermion compounds.
Non-ferrous metal
A non-ferrous metal is a metal or alloy in which iron is not the main constituent, such as copper, aluminum, brass, bronze, tin, silver, and zinc.
Non-fiction
Non-fiction: literature and media conveying information only about the real world; also nonfiction. Ranges from reference works to creative nonfiction, which applies fiction techniques to true stories; distinct from fiction by its factual claim.
Non-FIFA international football
Non-FIFA international football is representative football played by teams that are not FIFA members, such as Tibet, Tuvalu, and Cascadia, through the NF-Board and CONIFA.
Non-fullerene acceptor
A non-fullerene acceptor (NFA) is an organic electron-accepting molecule that replaces fullerene derivatives in organic solar cells, whose tunable properties have pushed power conversion efficiencies past 20%.
Non-functional requirement
A non-functional requirement (NFR), also called a quality requirement, is a software requirement describing how well a system performs, covering qualities like performance, security, and usability.
Non-functioning neuroendocrine tumor of pancreas
Non-functioning neuroendocrine tumor of pancreas (nonfunctioning PNET, NF-Pan-NET, ORPHA:506075): a well-differentiated pancreatic neuroendocrine neoplasm of at least 0.5 cm without hormonal syndrome, usually found incidentally, diagnosed by synaptophysin and chromogranin A staining, and managed by surveillance or surgery.
Non-functioning paraganglioma
Non-functioning paraganglioma: a catecholamine-nonproducing extra-adrenal neuroendocrine tumor, typically head and neck, often SDHD-related; diagnosed by imaging, managed with observation or surgery and imaging-based follow-up.
Non-functioning pituitary adenoma
Non-functioning pituitary adenoma (NFPA), also called clinically nonfunctioning pituitary tumor or nfPitNET, is a benign hormone-silent pituitary tumor causing mass effect: visual loss, headache, hypopituitarism; treated by transsphenoidal surgery.
Non-fungible token
A non-fungible token (NFT) is a unique cryptographic token recorded on a blockchain that certifies ownership of an associated asset; the market peaked above $40 billion in 2021.
Non-GAAP financial measure
A non-GAAP financial measure is a number derived from a GAAP measure by adjusting components, such as net income excluding restructuring charges, and is often disclosed voluntarily outside audited financial statements.
Non-gae
Non-gae (논개) was a Joseon government gisaeng who, by tradition, killed a Japanese commander by leaping with him into the Nam River at Jinju in 1593.