ExpertGlossary terms starting with X

114 terms

  1. x The basic number of chromosomes in a polyploid series, monoploid/haploid = x; diploid = 2x; triploid = 3x; etc.
  2. X chromosome See: sex chromosome.
  3. X inactivation The normal inactivation of one of the two X chromosomes in females.
  4. X patent In the 46 years prior to the Great Fire of 1836, the United States government had issued about 10,000 patents.
  5. X Windows A system developed at MIT that allows applications to be displayed in windows and shared among different workstations and terminals.
  6. X Windows/Motif ARC/INFO and ArcView operate in the X Windows/Motif environment on all supported UNIX workstation platforms.
  7. X-Band A frequency band of microwave radiation in which radars operate.
  8. X-bits Unassigned overhead bits. Transmitters should code these bits as zeros while receivers are required to be capable of ignoring the value contained in these…
  9. X-dimension of recorded spot In facsimile systems, the effective recorded spot dimension measured in the direction of the recorded line.
  10. X-dimension of scanning spot In facsimile systems, the distance between the centers of adjacent scanning spots measured in the direction of the scanning line on the object.
  11. X-header User-defined, unofficial header field that exists in the message header. X-headers are not specifically mentioned in RFC 2822, but the use of an undefined…
  12. X-linked The presence of a gene on the X-chromosome.
  13. X-linked disease A genetic disease caused by a mutation on the X chromosome. In X-linked recessive conditions, a normal female "carrier" passes on the mutated X chromosome…
  14. X-ON/X-OFF Transmitter On/Transmitter Off (Telecomm/Computer term).
  15. X-Open Consortium An association of American and European vendors formed in 1984 to promote open systems.
  16. X-ray A type of high-energy radiation. In low doses, x-rays are used to diagnose diseases by making pictures of the inside of the body.
  17. X-Ray Background In solar-terrestrial terms, a daily average background X-ray flux in the 1 to 8 angstrom range.
  18. X-Ray Burst In solar-terrestrial terms, a temporary enhancement of the X-ray emission of the sun.
  19. X-ray crystallography The diffraction pattern of X-rays passing through a pure crystal of a substance.
  20. X-Ray Flare Class In solar-terrestrial terms, rank of a flare based on its X-ray energy output. Flares are classified by the order of magnitude of the peak burst intensity…
  21. X-Ray Laser (XRL) A laser that generates a beam or beams of x-rays. Also called an "X- raser ."
  22. x-ray therapy (...THAYR-uh-pee) A type of radiation therapy that uses high-energy radiation from x-rays to kill cancer cells and shrink tumors.
  23. X-Rays The part of the electromagnetic spectrum whose radiation has much greater frequencies and smaller wavelengths than those of ultraviolet radiation.
  24. x-y mount Synonym altazimuth mount.
  25. X.-series Recommendations Sets of data telecommunications protocols and interfaces defined by CCITT (now, ITU-T) Recommendations. Note: Some of the more common X.
  26. X.25 A standard protocol for data communications.
  27. X.400 ISO standard for electronic mail.
  28. X.400 Connector An Exchange component that is integrated with the message transfer agent (MTA) and can be configured to connect routing groups within Exchange, or to…
  29. X.400 Recommendations Defines the standard interfaces of an electronic messaging system. These recommendations specify the structure of a message handling system, message…
  30. X.400 transport stack Networking software required to support X.400 server-to-server message transport. [Exchange 5.5]
  31. X.500 A set of standards defining a distributed directory service, developed by the International Standards Organization (ISO).
  32. X.509 Certificate The International Organization for Standardization/International Telecommunication Union Standardization Department (ISO/ITU-T) X.
  33. X.509 Public Key Certificate The public key for a user (or device) and a name for the user (or device), together with some other information, rendered unforgeable by the digital…
  34. X.75 Gateway Service A protocol for network interworking which supports communication between adjacent networks and communication thru transit networks.
  35. x86 architecture a computer hardware platform based on the Intel family architecture begun with the 8086 and continuing to the Pentium and later families.
  36. Xalan XSLT stylesheet processor. For more information, see http://xml.apache.org/xalan-j/
  37. Xanax (ZAN-ax) A drug used to treat anxiety disorders and panic attacks. It is being studied in the treatment of nausea and vomiting caused by some cancer…
  38. xanthophyll A yellow oxygen-containing carotenoid, present in chloroplasts.
  39. XBR X-Band Radar.
  40. XBT Expendable Bathythermograph
  41. XCITED Excited
  42. XCPT Expecting
  43. XCVR Transceiver.
  44. XDS Exoatmospheric Defense System.
  45. Xeloda (zeh-LOH-duh) A drug used to treat stage III colon cancer in patients who had surgery to remove the cancer.
  46. Xen Xen is an open source implementation of virtualization that is freely available at www.xensource.com.
  47. xenia The immediate effect of pollen on some characters of the endosperm.
  48. xenobiotic A chemical compound that is not produced by, and often cannot be degraded by, living organisms.
  49. Xenocurrency Xenocurrency is currency that trades outside of its own borders.
  50. xenogeneic Refers to organ s, genetically engineered ("humanized") todecrease the chance of rejection, that have been grown in an animal of another species for…
  51. Xenograft The cells of one species transplanted to another species.
  52. Xenotransplantation The transplantation of tissue or organs from one species to another species, typically from pigs to humans. Zoonoses are an important issue.
  53. Xenotransplantion A transplant of tissue from an animal of one species to an animal of another species.
  54. Xenu A software tool to check broken links.
  55. Xenu Link Sleuth Popular free software for checking a site for broken internal or external links and creating a sitemap. See also: Xenu - official site
  56. Xerces Advanced parsing. For more information, see http://xerces.apache.org/xerces-j/.
  57. Xeric (habitat) Low in moisture. Dry environmental conditions. Habitats or sites characterized by their limited water availability.
  58. Xeriscape Landscaping that does not require a lot of water.
  59. xeroderma pigmentosum (ZEER-oh-DER-ma pig-men-TOH-sum) A genetic condition marked by an extreme sensitivity to ultraviolet radiation, including sunlight.
  60. xerogram A picture of the body recorded on paper rather than on film. Also called xeroradiograph.
  61. xerographic recording Recording enabled by the scanning action of an optical beam on a photoconducting surface on which an electrostatically charged latent image is developed…
  62. xerophyte A plant very resistant to drought, typically adapted to extremely dry environments.
  63. xeroradiograph A picture of the body recorded on paper rather than on film. Also called xerogram.
  64. xeroradiography (zeer-oh-RAY-dee-AH-gruh-fee) A type of x-ray in which a picture of the body is recorded on paper rather than on film.
  65. xerostomia Dry mouth. It occurs when the body is not able to make enough saliva.
  66. XGA Extended Graphics Array.
  67. XHTML An XML look-alike for HTML defined by one of several XHTML DTDs. To use XHTML for everything would of course defeat the purpose of XML, because the idea…
  68. Xindice Native XML database. For more information, see http://xml.apache.org/xindice/.
  69. XIWT Cross Industry Working Team.
  70. XK469R A substance that is being studied in the treatment of leukemia. It belongs to the family of drugs called topoisomerase inhibitors.
  71. XL880 A substance being studied in the treatment of cancer. XL880 blocks enzymes involved in the growth and spread of tumor cells and in the growth of new blood…
  72. XLink The part of the XLL specification that is concerned with specifying links between documents.
  73. XLL The XML Link Language specification, consisting of XLink and XPointer.
  74. XML See Extensible Markup Language.
  75. XML (Extensible Markup Language) A markup language that enables users to tag data in order to delimit it, leaving the interpretation of the data to the applications that read it.
  76. XML Path Language (XPath) XPath is a language for finding information in an XML document. XPath is used to navigate through elements and attributes in an XML document.
  77. XML registry See registry.
  78. XML Schema The W3C specification for defining the structure, content, and semantics of XML documents.
  79. XML searching The ability to search into XML structures, including hierarchical content structures. Industry standards for XML searching includes XPath and XQuery.
  80. XML-APIs For more information, see http://www.apache.org.
  81. XML-RPC For more information, see http://www.apache.org.
  82. XML::DB Provides an XML persistance layer using the postgresql database. For more information, see http://xmldb.sourceforge.net/.
  83. XMLSec For more information, see http://www.apache.org.
  84. XMTR/CVR Transmitter/Receiver.
  85. XO Executive Officer.
  86. XoDis Exoatmospheric Discrimination.
  87. XOFF An abbreviation for the ASCII transmission-control character meaning "Transmitter off."
  88. XON An abbreviation for the ASCII transmission-control character meaning "Transmitter on."
  89. XOX Assistant Deputy Chief of Staff for Operations (Office Code).
  90. XP or Exp Experience Points
  91. XPath An addressing mechanism for identifying the parts of an XML document.
  92. XPath (XML Path Language) A language that uniquely identifies or addresses parts of a source XML document.
  93. XPC Expect
  94. XPG3 An X/Open software standard for UNIX Operating Systems. IBM provides a cshell variable named PSALLOC to make AIX XPG3-compliant, resulting in adding more…
  95. XPointer The part of the XLL specification that is concerned with identifying sections of documents so that they can be referenced in links or included in other…
  96. XR9576 A substance that is being studied in the treatment of cancer. It may help tumor cells respond again to drugs they have become resistant (unable to…
  97. XRL See X-Ray Laser.
  98. XRP9881 A substance that is being studied in the treatment of breast cancer. It belongs to the family of drugs called taxane derivatives.
  99. XRS USAF/ESC Staff Symbol.
  100. XS An extraordinarily exported, expeditiously excellent, expressly eXternal Subroutine, executed in existing C or C++ or in an exciting new extension…