District heating or coolingA system that involves the central production of hot water, steam, or chilled water and the distribution of these transfer media to heat or cool buildings.
disturbance voltageAn unwanted voltage induced in a system by natural or man-made sources. Note: In telecommunications systems, the disturbance voltage creates currents that…
disulfiramA drug that slows the metabolism of retinoids, allowing them to act over a longer period of time.
disulphide bridgeA chemical bond between pairs of sulphur atoms that stabilizes the three-dimensional structure of proteins, and hence the protein 's normal function.
DitheringIn printing, dithering is usually called halftoning, and shades of gray are called halftones.
DITPDiscriminating Interceptor Technology Program. The objective of DITP is the development of advanced interceptor seekers to counter advanced threats.
ditypeIn fungi, a tetrad that contains two kinds of meiotic products (spores), e.g. 2AB and 2ab.
diureticA drug that increases the production of urine.
Diurnal CyclesVariations in meteorological parameters such as temperature and relative humidity over the course of a day which result from the rotation of the Earth…
diurnal phase shiftThe phase shift of electromagnetic signals associated with daily changes in the ionosphere.
Diurnal Temperature RangeThe temperature difference between the minimum at night (low) and the maximum during the day (high).
divergenceThe expansion or spreading out of a vector field; usually said of horizontal winds. It is the opposite of convergence.
DiversificationThe investment in a number of different securities. To reduce the risk of loss inherent in investing.
Diversified Mutual FundThis is a mutual fund that does not have a stated policy of concentrating its investments in one industry, business, single country other than the U.S.
DiversionThe process of removing some minor criminal, traffic or juvenile cases from the full judicial process, on the condition that the accused undergo some sort…
Diversion capacityThe flow which can be passed through the canal headworks at a dam under normal head.
Diversion channel (canal or tunnel)A waterway used to divert water from its natural course. The term generally applies to a temporary arrangement (e.g.
Diversion damA dam built to divert water from a waterway or stream into a different watercourse.
Diversion inletA conduit or tunnel upstream from an intake structure. Diversion inlet may be integral with the outlet works or be part of a separate conveyance structure…
DiversityThe distribution and abundance of different plants and animals within an area.
diversity combinerA circuit or device for combining two or more signals carrying the same information received via separate paths or channels with the objective of…
Diversity FactorThe ratio of the sum of the noncoincidental maximum demands of two or more loads to their coincidental maximum demands for the same period.
diversity gainIn radio communications, the ratio of the signal field strength obtained by diversity combining to the signal strength obtained by a single path.
Diversity of citizenshipThe condition when the party on one side of a lawsuit is a citizen of one state and the other party is a citizen of another state; such cases may be under…
diversity receptionRadio reception in which a resultant signal is obtained by combining or selecting signals, from two or more independent sources, that have been modulated…
diversity transmissionRadio communication using a reception technique in which a resultant signal is obtained by combining signals (a) that originate from two or more…
Diversity VisaVisas based on a lottery system rather than a previously filed petition. Applicants enter themselves only once annually.
Diversity Visa (DV) ProgramThe Department of State has an annual lottery for immigration to the United States.
DivertTo direct a flow away from its natural course.
diverticulosisA condition marked by small sacs or pouches (diverticula) in the walls of an organ such as the stomach or colon.
divestitureThe court-ordered separation of the Bell Operating Telephone Companies from AT&T.
DivideA ridge or high area of land that separates one drainage basin from another.
divide and conquerAn approach to problem solving that attempts to reduce an overall single large problem into multiple simpler problems.
dividend fundA mutual fund that holds preferred and common stock that generally pay regular dividends.
Dividend payout ratioYou can calculate a dividend payout ratio by dividing the dividend a company pays per share by the company's earnings per share.
Dividend receipts from the rest of the worldReceipts received by U.S. residents of dividends from foreign corporations plus earnings distributed by unincorporated foreign affiliates to their U.S.
Dividend reinvestment plan (DRIP)Many publicly held companies allow shareholders to reinvest dividends in company stock or buy additional shares through dividend reinvestment plans, or…
Dividend yieldIf you own dividend-paying stocks, you figure the current dividend yield on your investment by dividing the dividend being paid on each share by the…
DividendsPayments in cash or other assets, excluding the corporation's own stock, made by corporations located in the United States and abroad to stockholders who…
Dividing StreamlineIn the blocked flow region upwind of a mountain barrier, the streamline that separates the blocked flow region near the ground from the streamlines above…
Dividing Streamline HeightThe height above ground of the dividing streamline, as measured far upwind of a mountain barrier. See dividing streamline.
DivisionDivision means the Wage and Hour Division (WHD) of the U.S. Department of Labor.
Division of Community Based Programs (DCBP)The division within HRSA's HIV/AIDS Bureau that is responsible for administering Part C, Part D, and the HIV/AIDS Dental Programs (the Dental…
Division of Science and Policy (DSP)The office within HRSA's HIV/AIDS Bureau that administers the Part F (SPNS) Program, HIV/AIDS evaluation studies, policy, and data reporting.
Division of Service Systems (DSS)The division within HRSA's HIV/AIDS Bureau that administers Part A and Part B of the Ryan White HIV/AIDS Program.
divisional applicationa later application for an independent or distinct invention disclosing and claiming (only a portion of and) only subject matter disclosed in the earlier…
dizygotic twinsTwo-egg twins, i.e. a pair of individuals that shared the same uterus at the same time, but which arose from separate and independent fertilization of two…
DJ-927A substance being studied in the treatment of cancer. It is a type of taxane derivative.
DM (document management)Techniques used to regulate the creation, use, and maintenance of documents according to established policies and procedures See also electronic document…
DMA (Direct Memory Access)The fastest method of data transfer available for multitasking operating systems.
DMC (Destination Management Company)A local company that handles arrangements for tours, meetings, transportation, etc. for groups originating elsewhere.
DMO (Destination Marketing Organization)A company or other entity involved in the business of increasing tourism to a destination or improving its public image(such as a convention and visitor…
DMOZThe Open Directory Project is the largest human edited directory of websites. DMOZ is owned by AOL, and is primarily ran by volunteer editors.
DNAThe molecules inside cells that carry genetic information and pass it from one generation to the next. Also called deoxyribonucleic acid.
DNA (deoxyribonucleic acid)An organic acid and polymer composed of four nitrogenous bases--adenine, thymine, cytosine, and guanine linked via intervening units of phosphate and the…
DNA / SerologySerology is the study of body fluids: blood, saliva, semen, and urine. From biological evidence left at a crime scene, such as hair or semen, DNA analysis…
DNA amplificationMany-fold multiplication of a particular DNA sequence either in vivo in a plasmid, phage or other vector; or in vitro using, most commonly, the polymerase…
DNA amplification fingerprinting(Abbreviation: DAF). A arbitrarily primed polymerase chain reaction technique for obtaining molecular markers using very short (5-8 bp) primers.
DNA bankA service that stores DNA extracted from blood samples or other human tissue.
DNA constructA chimeric DNA molecule, carrying all the genetic information necessary for its transgenic expression in a host cell.
DNA cytometry(si tom" eh tree') is a test sometimes used to help predict the aggressiveness of a tumor.
DNA delivery systemA generic term for any procedure that transports DNA into a recipient cell.
DNA diagnosisThe use of DNA polymorphisms to detect the presence of a disease gene.
DNA diagnosticsThe use of DNA polymorphisms to detect the presence of a specific sequence, which could indicate the presence of a contaminant, of a pathogen, or of a…