Science terms starting with A

1,045 terms

  1. Average energy The total power generation produced by a powerplant during all of the years of its actual or simulated operation divided by the number of years of actual…
  2. Average megawatt (MWa, aMW) One megawatt of capacity produced continuously over a period of one year. 1 aMW = 1 MW x 8760 hours/year = 8,760 MWh = 8,760,000 kWh.
  3. Average value Average value Arithmetic mean (m) of a number (n) of values (x1, x2, ... xn), defined by the equation: m = Sxi/n.
  4. Average Wind Speed (or Velocity) The mean wind speed over a specified period of time.
  5. Average year supply The average annual supply of a water development system over a long period.
  6. Average year water demand Demand for water under average hydrologic conditions for a defined level of development.
  7. AVG Average
  8. AVHRR Advanced Very High Resolution Radiometer. Main sensor on U.S. polar orbiting satellites.
  9. Avian Having to do with birds.
  10. Aviation gasoline All special grades of gasoline for use in aviation reciprocating engines, as given in the American Society for Testing and Materials (ASTM) specification…
  11. avidin A glycoprotein present in egg white, which has a strong affinity to biotin. Can lead to biotin deficiency if given in large quantities.
  12. avidity A measure of the binding strength of an antibody to its antigen.
  13. avirulence gene (Abbreviation: avr gene). Many plants contain R genes, which confer simply-inherited resistance to a specific pathogen race.
  14. AVN The Aviation model (120-hour numerical model of the atmosphere). The output from this model is now part of what is known as the GFS model.
  15. Avoid Harm Executive Order 13158 mandates that each federal agency whose actions affect an MPA shall, to the extent permitted by law and to the maximum extent…
  16. Avoided Cost The incremental cost to an electric power producer to generate or purchase a unit of electricity or capacity or both.
  17. Avoided costs An investment guideline describing the value of a conservation or generation resource investment by the cost of more expensive resources that a utility…
  18. Avoirdupois weight An English and American system of weights based on a pound of 16 ounces.
  19. AVP On a buoy report, Average Wave Period is the average period (seconds) of the highest one-third of the wave observed during a 20 minute sampling period.
  20. avr gene Abbreviation for avirulence gene.
  21. Avuncular relationship The genetic relationship between nieces and nephews and their aunts and uncles.
  22. AWARDS Agricultural Water Resources Decision Support.
  23. AWC Aviation Weather Center
  24. AWG The abbreviation for American Wire Gauge; the standard for gauging the size of wires (electrical conductors).
  25. AWHPS Area Wide Hydrologic Prediction System
  26. AWIPS Advanced Weather Interactive Processing System. This system replaced the Automation of Field Operations and Services (AFOS).
  27. Awning A metal frame clad with fabric attached over a window, door, porch opening or storefront to provide protection from the weather.
  28. AWOL absence without leave.
  29. AWOS Automated Weather Observation System
  30. AWTR Advanced Water Treatment Research.
  31. AWWA American Water Works Association.
  32. axenic culture Free of external contaminants and internal symbionts; generally not possible with surface sterilization alone, sometimes used incorrectly to indicate.
  33. Axial Fans Fans in which the direction of the flow of the air from inlet to outlet remains unchanged; includes propeller, tubaxial, and vaneaxial type fans.
  34. Axial Flow Compressor A type of air compressor in which air is compressed in a series of stages as it flows axially through a decreasing tubular area.
  35. Axial Flow Turbine A turbine in which the flow of a steam or gas is essentially parallel to the rotor axis.
  36. axillary bud A bud found at the axil of a leaf. Synonym: lateral bud.
  37. axillary bud proliferation Propagation of plant tissue in vitro to promote axillary growth, to generate large numbers of plantlets in culture.
  38. Axis A straight line passing through a spherical body between its two poles. The central line of the body or any of its parts. The vertebral column.
  39. Axis of Dam A vertical plane or curved surface, appearing as a line in plan or cross section, to which horizontal dimensions can be referred.
  40. Axis of dam (concrete) A vertical reference surface coincident with the upstream face at the top of the dam.
  41. Azimuth A direction in terms of a 360° compass. North is at 0°, east is at 90°, south is at 180°, and west is at 270°.
  42. Azimuth (Solar) The angle between true south and the point on the horizon directly below the sun.
  43. Azimuth Angle The direction or bearing toward which a sloping surface faces (e.g., a north-facing slope has an azimuth angle of 360°; a northeast-facing slope, an…
  44. Azores Current One of the currents of the North Atlantic subtropical gyre.
  45. Azores High Alternate term for Bermuda High - a semi-permanent, subtropical area of high pressure in the North Atlantic Ocean off the East Coast of North America that…