Aquifer-carbonate rockAn aquifer found in limestone and dolomite rocks. Carbonate aquifers typically produced hard water, that is, water containing relatively high levels of…
Aquifer-confinedSoil or rock below the land surface that is saturated with water. There are layers of impermeable material both above and below it and it is under…
Aquifer-unconfinedAn aquifer whose upper water surface (water table) is at atmospheric pressure, and thus is able to rise and fall.
Aquifer-volcanic rockAn aquifer in which the rock matrix is composed of volcanic rocks, (e.g., tuffs or basalt flows).
AquifugeA geologic formation which has no interconnected openings and cannot hold or transmit water.
ArabidopsisA genus of flowering plants in the Cruciferae. A. thaliana is used in research as a model plant because it has a small fully sequenced genome, can be…
arabinanThe polymer of arabinose with a repeating unit of C5H804. Can be hydrolyzed to arabinose. (Source: Voet, D.; Voet, J. G. Biochemistry.
arabinoseA five-carbon sugar - C5H1005. A product of hydrolysis of arabinan found in the hemicellulose fraction of biomass.
ArableSuitable for farming. Having soil or topographic features suitable for cultivation.
Arable landLand which when farmed in adequate size units for the prevailing climatic and economic setting, and provided with the essential on-farm improvements of…
Arable landsRefers to all lands generally under rotation whether it is under temporary crops, temporarily fallowed, or used as temporary meadows.
aramid yarnGeneric name for a tough synthetic yarn that is often used in optical cable construction for the strength member, protective braid, and/or rip cord for…
ARARapplicable or relevant and appropriate requirement.
ArbitrageArbitrage is the technique of simultaneously buying at a lower price in one market and selling at a higher price in another market to make a profit on the…
arbitrary markscomprise words that are in common linguistic use but, when used to identify particular goods or services, do not suggest or describe a significant…
arbitrary primerAn oligonucleotide primer whose sequence is chosen at random, rather than one whose sequence matches that of a known locus.
Arbitrated loopA basic configuration of Fibre Channel networks in which up to 126 devices can share a single segment or loop, with one additional node left for linkage…
ArbitrationThe process in which a third-party arbiter examines facts presented by both you and the insurance company when you disagree about a settlement offer.
ArbitratorA private, disinterested person chosen by the parties in arbitration to hear evidence concerning the dispute and to make an award based on the evidence.
arc(1) Advanced Research Center, US Army, Huntsville, AL. (2) Atlantic Research Corporation.
Arc Attribute Table (AAT)A table containing attributes for arc coverage features. In addition to user-defined attributes, the AAT contains the from and to nodes, the left and…
Arc Code (ACODE) fileAn INFO data file storing arc attributes for coverages created from TIGER, DIME, IGDS and Etak files. ACODE stands for 'Arc CODE'.
Arc Digitizing System (ADS)A simple digitizing and editing system used to add arcs and label points to a coverage. A command at the Arc: prompt that starts an ADS session.
ARC Macro Language (AML)A high-level algorithmic language for generating end-user applications. Features include the ability to create on-screen menus, use and assign variables…
ARC Standard Raster Graphic (ASRG)Raster graphic data transformed to the Equal ARC-second Raster Chart/Map (ARC) Projection System. See SRG.
arc-node topologyThe topological data structure ARC/INFO uses to represent connectivity between arcs and nodes.
ArchA fingerprint pattern in which the friction ridges enter from one side, make a rise in the center, and exit on the opposite side.
Arch DamA concrete or masonry dam which is curved upstream in plan so as to transmit the major part of the water load to the abutments and to keep the dam in…
Arch Filament System (AFS)In solar-terrestrial terms, a bright, compact plage crossed by a system of small, arched filaments, which is often a sign of rapid or continued growth in…
Arch-gravity damAn arch dam which is only slightly thinner than a gravity dam.
ArchaeaSingle-celled life forms adapted to existence in high pressure, anaerobic, environments such as at extreme ocean depths.
Archaeological siteAny location where humans have altered the terrain or discarded artifacts during prehistoric or historic times.
ArchaicIn American archeology, a cultural stage following the earliest known human occupation in the New World (about 5,500 B.C. to A.D. 100).
ArcheologyStudy of human cultures through the recovery and analysis of their material relics.
Archimedean screwAn ancient water-raising device attributed to Archimedes, made up of a spiral tube coiled about a shaft or of a large screw in a cylinder, revolved by…
ArchingThe transfer of stress from a yielding part of a soil or rock mass to adjoining less-yielding or restrained parts of the mass.
ArchitectAn individual, partnership, corporation or other legal entity licensed to practice the profession of architecture under the education law of the State of…
Architectural DesignThe process of defining a collection of hardware and software components and their interfaces to establish the framework for the development of a computer…
architectureThe term architecture refers to the hardware, software or combination of hardware and software comprising a computer system or network.
Architecture Integration Study (AIS)A study to determine the performance of alternative architectures and element designs that satisfy BMD System mission requirements, and to evaluate the…
Architrave1. The lowest part of a classical entablature. 2. A molding enframing an opening such as a window or areaway or the open space between a rowhouse and the…
archival authorityAgency or program responsible for selecting and preserving archives, making them available, and approving destruction of other records
Archival DataArchival Data is information an organization maintains for long-term storage and record keeping purposes, but which is not immediately accessible to the…
archival integrityprinciple that a body of records resulting from the same activity must be preserved as a group, without division, separation, or addition to protect the…
archival mediuma material recording medium that has been approved for archival use because it has been tested and proven to offer a high degree confidence in the…
archival processingThe activities of accessioning, arranging, describing, conducting access review, and properly storing documentary material.
Archival storageStorage conditions specifically designed to extend or maximize the lifetime of stored media.
archival valueThe determination by appraisal that records are worthy of permanent preservation by the Office of State Archives. See also historical value.
archiveA copy of data (any information stored on a computer) on a computer drive, or on a portion of a drive, maintained for historical reference.
archive fileA software file that has been set aside, often in a redundant storage medium, as a security measure or for later retrieval, e.g.
archive writera [Kodak] trade name for a device that converts digital records to computer output microfilm.
Archive/Electronic ArchiveArchives are long term repositories for the storage of records. Electronic archives preserve the content, prevent or track alterations and control access…
archivesThe documents created or received and accumulated by a person or organization in the course of the conduct of affairs and preserved because of their…
archives administrationthe same as archives management, although it often refers more narrowly and particularly to the administration of staff, budgets, facilities, logistics…
archives managementthe management of acquiring and maintaining permanent records in an archives and making them available for public inspection.
ArchiveSinkA diagnostic tool that can be used to log all message and recipient details of an e-mail message for incoming and outgoing messages on an Exchange server.
archivingreducing the strain of storing data by backing it up, removing it from its native environment, and storing it elsewhere. [...
archivistA person professionally occupied in the administration of archives and/or management of archives See also Certified Archivist (CA) and records manager.
ArcStormArcStorm (ArcStorageManager) is a data storage facility and transaction manager for ARC/INFO data.
ArcStorm databaseAn ArcStorm database is a collection of libraries, layers, INFO tables and external DBMS tables.
ArcticThe region within the Arctic Circle, or, loosely, northern regions in general, characterized by very low temperatures.
arctic airA very cold and dry air mass that forms primarily in winter and the northern interior of North America.
Arctic air massArctic air mass Mass of very cold air in the Arctic regions which invades lower latitudes at irregular intervals.
Arctic CircleArctic Circle The line of latitude 66° 32' N (often taken as 66.5° N). Along this line the Sun does not set on the day of the summer solstice, and does…
Arctic frontThe boundary or front separating deep, cold arctic air from shallower, relatively less cold polar air.
Arctic hazeArctic haze Haze in Arctic regions which reduces horizontal and slant visibility and which may extend to a height of about 10 km.
Arctic highArctic high A weak high which appears over the Arctic Basin during late spring, summer and early autumn, one of the centers of action in the atmosphere.
Arctic mistArctic mist A mist of ice crystals; a very light ice fog.
Arctic Oscillation(abbrev. AO)- The Arctic Oscillation is a pattern in which atmospheric pressure at polar and middle latitudes fluctuates between negative and positive…
Arctic Sea SmokeSteam fog, but often specifically applied to steam fog rising from small open water within sea ice.
Arctic tundraA treeless area between the icecap and the tree line of Arctic regions that has permanently frozen subsoil and supports low-growing vegetation such as…
arctigeninA substance found in certain plants, including burdock. It has shown antiviral and anticancer effects.
arctiinA substance found in certain plants, including burdock. It has shown anticancer effects. Arctiin belongs to a group of substances called lignans.
ArcToolsArcTools is a collection of ARC/INFO productivity tools implemented through an AML-based (ARC Macro Language) graphical user interface.
ArcusA low, horizontal cloud formation associated with the leading edge of thunderstorm outflow (i.e., the gust front).
AreaMust have legally defined geographical boundaries, and may be of any size, except that the site must be a subset of the U.S.
Area Air Defense Commander (AADC)The person given overall responsibility for air defense within an overseas unified command, subordinate unified command, or a joint task force.
area broadcast shiftThe changing from listening to transmissions intended for one broadcast area to listening to transmissions intended for another broadcast area.
area codeSee access code, code, country code, N code.
Area DefenseDefense of a broad geographical area that contains both military and civilian assets (i.e., depots, towns/cities). (USSPACECOM)
Area Forecast DiscussionThis National Weather Service product is intended to provide a well-reasoned discussion of the meteorological thinking which went into the preparation of…
area lossWhen optical fibers are joined by a splice or a pair of mated connectors, a power loss that is caused by any mismatch in size or shape of the cross…