ExpertGlossary terms starting with H

1,452 terms

  1. hash value In cryptography, the result of applying a cryptologic hash function to a message. [After X9.31]
  2. Hash-based Message Authentication Code (HMAC) A specific construction for calculating a message authentication code (MAC) involving a cryptographic hash function in combination with a secret key.
  3. Hashing The process of using a mathematical algorithm against data to produce a numeric value that is representative of that data.
  4. hashword [The] memory address containing [a] hash total. [INFOSEC-99]
  5. HASP Hardened Ada Signal Processor.
  6. Hatch Act The Hatch Act places restrictions on political activity by employees of the executive branch of the U.S.
  7. Hatchery A facility where fish and raised for stocking.
  8. Hate Similar to threat
  9. HATELM High-speed Anti-TEL Missile.
  10. HATMD High-Altitude Theater Missile Defense. (U.S. Army)
  11. Haul distance The distance measured along the center line or most direct practical route between the center of the mass of excavation and the center of mass of the fill…
  12. Hauler The 18-wheel tractor-trailer rig that teams use to transport two race cars, engines, tools and support equipment to the racetrack.
  13. Haunches (haunch) The outside areas between the springline and the bottom of a pipe. In pipe, the sides of the lower third of the circumference.
  14. HAVE STARE Name assigned a proven sensor capability.
  15. having (used when defining the scope of a claim) A transitional phrase that is synonymous with (means the same thing as) "including," "containing" or…
  16. Hawaii Capital Loan Program (HCLP) Authorized by state law, this loan program is administered by the State Department of Business, Economic Development & Tourism to assist small businesses…
  17. hawg A slang term describing a large lunker-size or heavyweight bass weighing 4 pounds or more.
  18. HAWK Homing All-the-Way Killer.
  19. Hawkeye A monitoring service for Condor Pools. See http://www.cs.wisc.edu/condor/hawkeye/.
  20. hawthorn fruit The fruit of the hawthorn tree or bush. It has been used in some cultures to treat certain medical problems, including heart problems and gastrointestinal…
  21. Hazard Something (e.g., a dam) that creates the potential for adverse consequences such as loss of life (LOL), property damage, and adverse social and…
  22. Hazard classification The rating for a dam based on the potential consequences of failure. The rating is based on potential for loss of life and damage to property that failure…
  23. Hazard Insurance insurance that is generally required under mortgage contracts to pay for loss or damage to a person’s home or property.
  24. Hazard Insurance/Homeowners Insurance Insurance coverage that provides compensation to the insured in case of property loss or damage.
  25. Hazard Ranking System (HRS) The Hazard Ranking System (HRS) is the principal mechanism EPA uses to place waste sites on the NPL.
  26. hazard ratio (HA-zurd RAY-shee-oh) A measure of how often a particular event happens in one group compared to how often it happens in another group, over time.
  27. Hazardous air pollutant (HAP) Substances that have adverse impacts on human health when present in ambient air.
  28. Hazardous material Any material that poses a threat to human health and/or the environment. Hazardous materials are typically toxic, corrosive, ignitable, explosive, or…
  29. Hazardous materials Materials that pose the potential for grave, immediate, future, and genetic injury and illness when handled without proper equipment and precautions.
  30. Hazardous Substance Research Centers ((HSRC)): Hazardous Substance Research Centers (HSRC) are a set of national organizations that carry out an active program of basic and applied research…
  31. Hazardous substances Element or compound other than oil which when discharged into the environment, in any quantity, presents an imminent or substantial threat to public…
  32. Hazardous waste By-products of society that can pose a substantial or potential hazard to human health or the environment when improperly managed.
  33. Hazardous Waste Indicators Indicators that may signal the presence of hazardous materials include stressed vegetation or unusual lack of vegetation; dead or sick domestic stock…
  34. Hazardous waste sites Any spill, authorized or unauthorized dumping, abandoned, or inactive waste disposal sites containing or suspected of containing hazardous materials.
  35. Hazardous Weather Outlook A narrative statement produced by the National Weather Service, frequently issued on a routine basis, to provide information regarding the potential of…
  36. Hazards Assessment CPC's Hazards Assessment provides emergency managers, planners, forecasters and the public advance notice of potential hazards related to climate, weather…
  37. hazards of electromagnetic radiation to fuel (HERF) The potential for electromagnetic radiation to cause ignition or detonation of volatile combustibles, such as aircraft fuels.
  38. hazards of electromagnetic radiation to ordnance (HERO) The potential for electromagnetic radiation to affect adversely munitions or electroexplosive devices.
  39. hazards of electromagnetic radiation to personnel (HERP) The potential for electromagnetic radiation to produce harmful biological effects in humans.
  40. Haze (abbrev. HZ)- An aggregation in the atmosphere of very fine, widely dispersed, solid or liquid particles, or both, giving the air an opalescent appearance…
  41. HBA Host Bus Adapter. Any hardware bridge between a storage interconnect and a system's I/O bus.
  42. HBA (Host Bus Adapter) "Host Bus Adapter", connects a host system (the computer) toother network and storage devices.
  43. HBCU/MI Historically Black Colleges and Universities/Minority Institutions.
  44. HBHO Hard-body Hand-over [algorithms].
  45. HCA A chemical that is formed when meat, poultry, or fish is cooked at high temperatures, such as frying, broiling, and barbecuing.
  46. HCAP A protocol used by Access Control Server (ACS) to send and receive statements of health to and from other NAP infrastructure components.
  47. HCD (Hardware Configuration Definition) an interactive interface that enables an installation to define I/O configurations to both the software and hardware from one interface.
  48. HCD20 A monoclonal antibody that is being studied in the treatment of refractory B-cell non-Hodgkin lymphoma.
  49. HCEP The protocol used by the NAP agent to request health certificates from the Health Registration Authority (HRA) and to prove the health of a client…
  50. hCNS Human central nervous system stem cell.
  51. HCO High Consequence Option (Safety Engineering term).
  52. HCP Healthcare proxy. A type of advance directive that gives a person (such as a relative, lawyer, or friend) the authority to make healthcare decisions for…
  53. hCRF A substance being studied in the treatment of brain cancer. It is made naturally by the hypothalamus (a part of the brain) and can also be made in the…
  54. HCT Mercury Cadmium Telluride.
  55. HD (High Density) A 5.25 HD Floppy Disc holds 1.2 MB and a 3.5 holds 1.4 MB.
  56. HDA Hybrid Detector Assembly.
  57. HDA (Head/Disk Assembly) a sealed Winchester assembly, including disks, heads, filter and actuator assembly.
  58. HDAC An enzyme that changes the way histone binds to DNA. HDAC inhibitors are being studied as a treatment for cancer. Also called histone deacetylase.
  59. HDAC inhibitor (...in-HIH-bih-ter) A substance that causes a chemical change that stops tumor cells from dividing.
  60. HDBK Handbook.
  61. HDD Heating Degree Days- A form of degree day used to estimate energy requirements for heating.
  62. HDD (Hard Disk Drive) , also called a Winchester drive, is a spinning magnetic disk accessed by a flying head.
  63. HDL (or high-density lipoprotein ) A combined protein and fatlike substance. Low in cholesterol, it usually passes freely through the arteries. Sometimes called "good cholesterol."
  64. HDLC Abbreviation for high-level data link control.
  65. HDR An amount of radiation that is greater than that given in typical radiation therapy.
  66. HDRAIN An Hourly Digital Rainfall Product of the WSR-88D.
  67. HDTV Abbreviation for high-definition television.
  68. HDX Half Duplex ( TelComm /Computer term).
  69. HE (1) High Explosive. (2) High Energy.
  70. HE11 mode Designation for the fundamental hybrid mode of an optical fiber.
  71. Head The upper horizontal part of a window frame or window opening.
  72. head and neck cancer Cancer that arises in the head or neck region (in the nasal cavity, sinuses, lips, mouth, salivary glands, throat, or larynx [voice box]).
  73. Head clog Debris trapped in the playback head of a video recorder. Clogging of the playback head with debris causes dropouts.
  74. head end See cable headend, headend.
  75. Head Log The heavily reinforced section at each end of the barge and in the bow of the towboat to take the pressure of pushing the tow.
  76. Head Loss The energy lost from a flowing fluid due to friction, transitions, bends, etc.
  77. Head of household Head of household is an IRS filing status that you can use if you are unmarried or considered unmarried on the last day of a tax year and provide at least…
  78. Head of Household filing status You must meet the following requirements: 1. You are unmarried or considered unmarried on the last day of the year. 2.
  79. Head Race A channel which directs water to a water wheel; a forebay.
  80. Head wrench Slang term used for a race team's crew chief.
  81. head-of-bus function The function that generates management information and empty bus slots at the point on each bus where data flow begins.
  82. head-on collision A collision that occurs on a communications channel when two or more users begin to transmit on the channel at approximately the same instant.
  83. headend A central control device required by some networks (e.g., LANs or MANs) to provide such centralized functions as remodulation, retiming, message…
  84. Header A masonry wall unit of brick which is laid so that its short end is exposed.
  85. header check sequence (HCS) A 16-bit cyclic redundancy check (CRC) check sequence (CS) that is derived from bits from the first 8 octets (excluding flags) of a UIH format packet. [T1.
  86. header file A file containing certain required definitions that you must include "ahead" of the rest of your program to do certain obscure operations.
  87. Heading In a tunnel, a digging face and its work area.
  88. Heading tag An HTML tag that is often used to denote a page or section heading on a web page.
  89. Headings The heading element briefly describes the subject of the section it introduces.
  90. headless Describes a program or application that runs in the background without any interface connected to it.
  91. Headline The title of an article or story.
  92. Headnote A brief summary of a legal rule or significant facts in a case, which, along with other headnotes, precedes the printed opinion in reports.
  93. Headrace. See forebay.
  94. Heads Up Playing alone against a dealer.
  95. Heads Up or Heads On A head to head play with the dealer - no other players are involved.
  96. Headwall An upstream wall.
  97. Headward Erosion Erosion which occurs in the upstream end of the valley of a stream, causing it to lengthen its course in such a direction.
  98. Headwater (1) The source and upper reaches of a stream; also the upper reaches of a reservoir; (2) the water upstream from a structure or point on a stream; (3) the…
  99. Headwater Advisory Program (ADVIS) A Program which uses the Antecedent Precipitation Index (API) method of estimating runoff, unit hydrograph theory and stage-discharge ratings to produce…
  100. Headwater Advisory Table A table developed by a River Forecast Center for a Headwater Guidance Point; a pre-computed matrix of values allows a forecaster to ascertain an…