XAA	eXtreme Activity Addict
XAA	X Acceleration Architecture
XAB	X11 Address Book
XAC	X Automatic Code
XAD	eXperimental Attack Divebomber
XAE	XML Authoring Environment
XAF	eXtensible Application Framework
XAG	X-Media Asset Group
XAI	X-ray Analysis Integration
XAL	X10 Abstraction Library
XAM	eXceptional Asian Market
XAM	eXtensible Access Method
XAO	eXperimental Airplane-Observation
XAP	Xenotransplantation Action Plan
XAQ	Xanalogically Asked Question
XAR	XML ARchive
XAS	X-ray Absorption Spectroscopy
XAT	eXperimental Advanced Trainer
XAW	eXchange And Warranty
XAX	eXcellence Above eXpectation
XAZ	X-ray Analysis Zone
XBA	eXtra Bases Advanced
XBA	eXtreme Bandwidth Architecture
XBC	Cross-Border Connection [!]
XBC	eXtended Block Cache
XBE	eXpress Business Effectiveness
XBF	eXperimental Boundary File
XBF	eXtensible Binary Format
XBG	eXperimental Bomber-Great Lakes
XBH	eXtra-Base Hit
XBI	eXtended Basic Input
XBL	eXploits Block List
XBL	eXtensible Bindings Language
XBL	eXtreme spam Blocking List
XBM	eXtended Basic Mode
XBM	X [Window System] BitMap
XBP	XBase Parts
XBQ	X-Box Quebec
XBR	Cross-Band Radar [!]
XBR	eXperimental Brian Research
XBT	eXpendable BathyTHermograph
XBT	X-Bar Tandem
XBV	eXtreme Beach Volleyball
XBW	eXtreme Backyard Wrestling
XBZ	X-Box Zone
XCA	eXtreme Circumstances Allowance
XCB	eXtension Client Binding
XCC	eXpectation-value Coupled-Cluster
XCE	eXchange Carry and Emulation
XCF	Cross-system Coupling Facility [!]
XCF	eXperimental Computing Facility
XCG	Xenopus Cement Gland
XCI	XML Court Interface
XCK	eXtreme Chaos Kommando
XCL	eXcess Current Liabilities
XCM	eXternal ComMand
XCN	X-Chat Napsterizer
XCP	eXtended Copy Protection
XCP	Xen Cloud Platform
XCQ	eXecutive Control Quotient
XCR	Xilinx Cool Runner
XCS	Xenos Christian School
XCU	eXtreme Close Up
XCV	eXperimental Carrier Vessel
XCW	eXtreme Championship Wrestling
XCX	eXtreme Circumstances eXploration
XDA	X-band Drive Amplifier
XDB	eXtended DataBase
XDB	XML DataBase
XDC	Cross-point Data Conflict [!]
XDD	eXperimental Design Document
XDE	eXtended Development Experience
XDE	Xylene-Dioxane-Ethanol
XDF	eXtended Distance Feature
XDF	[IBM] eXtended Density Format
XDG	eXperimental Design Group
XDH	Xanthene DeHydrogenase
XDJ	Xerox Disclosure Journal
XDK	[Microsoft] X-Box [software] Development Kit
XDK	[Oracle] XML Developer Kit
XDL	X Display Location
XDM	X Display Manager
XDM	X-treme Dungeon Mastery
XDM	XML Documentation Mark-up
XDN	Xsonic Data Now
XDO	eXtensible Data Object
XDP	eXtended Data Processing
XDP	XML Data Package
XDR	eXtended Dynamic Range
XDR	eXternal Data Representation
XDR	XML Data-Reduced
XDS	X/Open Directory Service
XDS	Xerox Data Systems
XDT	Xenon Discharge Tube
XDW	Xerox DocuWorks
XDX	Xenon Discharge eXperiment
XDZ	Xian Development Zone
XEA	eXpress Electronic Access
XEC	eXperimental Estelle Compiler
XED	XML EDitor
XEE	XML External Entity
XEE	XML [Query] Execution Engine
XEF	XEnon Fluoride
XEG	X-ray Emission Gauge
XEH	XEnon Hydride
XEM	eXchange Electronic Mail
XEQ	eXtra Easy Question
XER	XML Encoding Rule
XES	Xerox Engineering Systems
XES	Xray Emission Spectra
XET	Xerox Ethernet Tunnel
XET	Xyloglucan EndoTransglycosylases
XEW	X Examine WAD
XFA	eXtremely Fast Access
XFA	XML Forms Architecture
XFB	aXway File Broker
XFB	eXtended File Broker
XFC	XMLmind FO Converter
XFC	XSL Formatting Composer
XFD	eXtreme Feedback Device
XFE	X Front End
XFF	eXtended Feature Function
XFG	X-band Frequency Generator
XFH	X-ray Fluorescence Holography
XFI	X-band Frequency Interference
XFL	eXtreme Football League
XFM	eXchange Force Microscopy
XFN	eXperimental Frazer-Nash
XFN	X/Open Federated Naming
XFO	XSL Formatting Object
XFQ	Xenon-Filled Quartz
XFR	eXperiments in the Future of Reading
XFR	eXtended Frequency Range
XFS	eXtended File System
XFS	eXtra Fast System
XFS	X [Window System] Font Server
XFT	eXtremely Fast Tracker
XFU	Xenon Flash Unit
XFV	eXperimental Fighter Vertical-takeoff
XFW	Crossing Fort Worth [!]
XFX	eXtra Effects [!]
XGA	eXtended Graphics Array
XGB	eXtreme Ghost Busters
XGC	eXtension of the Goldbach Conjecture
XGD	eXtended Graphics Display
XGE	eXogenous Genetic Engineer
XGF	XML Game Format
XGG	Xander Guardian Guild
XGH	eXtreme GoHorse
XGH	Xenopus Growth Hormone
XGI	Xenopus laevis Gene Index
XGK	X-Generation Kit
XGL	eXtra Grand Luxury
XGL	X over OpenGL
XGM	Cross-Gain Modulation [!]
XGN	eXtreme Gaming Network
XGP	Xylophone and Glockenspiel Players
XGQ	eX-Gentleman's Quarterly
XGR	eXtreme Gaming Radio
XGS	eXtreme Gaming Server
XGT	eXtreme God Team
XGV	Xerox Global View
XGX	eXtensible Graphics [!]
XGZ	Xenogears Ground Zero
XHA	Crossover High Availability [!]
XHB	XML HandBook
XHC	eXtra High Ceiling
XHD	eXtra Heavy-Duty
XHF	eXtra High Frequency
XHG	eXtra High-Grade
XHI	eXtra High Intensity
XHK	Xerox-Hong Kong
XHL	eXtensible Hyperlinking Language
XHM	Xantus Healthplan for Mississippi
XHP	eXpandable HomePage
XHP	X-rays and Health Project
XHQ	eXtreme High Quality
XHR	Xplizit Hardcore Recording
XHS	eXchangeable Hub System
XHV	eXtremely High Vacuum
XHW	eXtreme HardWare
XHY	eXtra High Yield
XIA	Xanadu Information Architecture
XIB	XML Inline Binary
XID	eXchange IDentification
XIE	X [Window System] Image Extension
XIF	Xerox Image File
XIG	XI Graphics
XIG	XML Interest Group
XIK	XRT Integration Kit
XIL	eXtensible Indexing Language
XIM	eXtensible Implementation Methodology
XIM	eXtra Information Management
XIM	X Input Methods
XIN	eXtended Intensive-care Nursing
XIO	eXtended Input-Output
XIP	eXecute-In-Place
XIP	[Intel] eXtended Instruction Pointer
XIQ	eXtreme Intelligence Quotient
XIR	XIAM Information Router
XIS	X-ray Isochromat Spectroscopy
XIS	[Excelon] eXtensible Information Server
XIU	Xian International University
XIZ	eXtra Initial Zero
XJC	XML Java Compiler
XJD	XML Job Description
XJE	X-frame Java Environment
XJG	Xassow Japan Guiding
XJI	eX Jocks, Incorporated
XJP	eXperimental Jet Pack
XJR	eXperimental Jaguar Racing
XJS	eXperimental Jaguar Sports
XJT	eXpansion JoinT
XJU	XinJiang University
XJW	eX-Jehovah's Witness
XJX	XML to Java Transformation [!]
XJY	eXchange of Japanese Yen
XKB	X KeyBoard [Extension]
XKI	eXtensible Key Infrastructure
XKM	XML Key Management
XLA	eXcimer LASER
XLB	Xylem-Limited Bacteria
XLC	eXcellence and Leadership for Communities
XLD	eXperimental LASER Device
XLE	XML Lightweight Extractor
XLF	eXtensible Log Format
XLF	[IBM] eXceptionaL Fortran
XLG	eXtra LarGe
XLH	X-Linked Hypophosphatemia
XLL	eXtended Linking Language
XLM	eXtra-Light Mountain
XLN	Xtra Low Noise [cable]
XLO	eXtra Large Orifice
XLP	X-Linked LymphoProliferation
XLQ	eXtra-Large Quotient
XLS	eXcimer LASER System
XLS	eXtended Light Scatterer
XLT	XML Lexicons and Terminologies
XLU	eXclusive of Loading and Unloading
XLV	eXtended Linux Video
XLW	eXceL Web
XLX	eXtra Learning eXperience
XMA	X-ray Micro-Analysis
XMB	XML Message Board
XMB	Xross Management Bar
XMC	Xpress Media Consulting
XMD	eXpert Mold Design
XMF	eXpanding Market Forces
XMG	Xavier Media Group
XMH	X-interface to Mail Handling
XMI	XML Metadata Interchange
XMI	[DEC] eXtended Memory Interconnect
XMK	eXtreme Minimal Kernel
XML	eXtensible Markup Language
XMM	eXtended Memory Manager
XMM	X-ray Multi Mirror
XMP	eXperimental Mathematical Programming
XMP	eXtended Management Pack
XMP	eXtensible Metadata Platform
XMP	eXtreme Memory Profile
XMP	X/open Management Protocol
XMQ	XPS MultiQuant
XMR	X-ray Magnetic Resonance
XMS	eXtended Memory Specification
XMS	eXtended Multiprocessor [Operating] System
XMU	XiaMen University
XMX	X MultipleXor
XNA	Xinghua News Agency
XNB	eXplore New Brunswick
XNC	eXperimental Numerical Control
XNC	X Northern Captain
XND	X-Men Next Dimension
XNE	Xiamen Ningly Electronics
XNF	Xilinx Netlist Format
XNH	eXperimental Nagler Helicopter
XNI	Xerces Native Interface
XNL	eX-National League
XNM	eXpansion Node Manager
XNN	Xena News Network
XNO	eXperimental Network Operation
XNP	eXperimental Network Protocol
XNP	eXtended Network Protocol
XNR	X-based News Reader
XNS	Xerox Network Services
XNU	eXclude Non-Unique
XNU	X's Not Unix
XNW	eXplorations NorthWest
XOA	eXperimental Observation Amphibian Aircraft
XOB	Xanopinauta Oro de Brasilia
XOC	eXtreme Over Clocker
XOC	Xterra Owners Club
XOD	eXternal Object Data
XOF	eXtendable Output Function
XOG	eXpedition Owners Group
XOH	eXperimental Observation Helicopter
XOI	eXplodes On Impact
XOJ	eXecutive Office-Joint Matters
XOL	XML-based Ontology-exchange Language
XOM	X/Open Object Management
XON	eXchange ON
XON	Transmitter On [!]
XOO	eXtended Operational Optimisation
XOP	X-rays Out of Plaster
XOP	XML-binary Optimized Packaging
XOQ	eXample of Order Query
XOR	eXclusive OR
XOS	eXperimental Operating System
XOT	X.25 Over TCP
XOT	X.25 Over TCP/IP
XOU	eXtra Output Unit
XOV	Crossover OverView [!]
XOW	XML Output Writer
XOX	X On X
XOY	eXecutive Officer Yeomanry
XOZ	eXtra Output Zero
XPA	X-band Planar Array
XPB	Xlib Playback Benchmark
XPC	eXplicitly Parallel C
XPC	eXtended Processing Cabinet
XPC	X Performance Characterization
XPC	X.25 Protocol Controller
XPD	Cross Polar Discrimination [!]
XPD	eXPedient Demise
XPE	eXtreme Performance Enhancement
XPE	[Microsoft Windows] XP Embedded
XPF	eXPlosion-release Factor
XPF	eXtended Packet Filter
XPG	eXcellent Personal Grooming
XPG	eXtreme Performance Gear
XPG	X.400 Promotion Group
XPG	X/Open Portability Guide
XPH	eXPlosion Hazard
XPI	eXtra Paranormal Investigation
XPI	Xerox Publishing Illustrator
XPK	eXternal PacKer
XPM	Cross-Phase Modulation [!]
XPM	X PixMap
XPM	[Windows 7] XP Mode
XPN	eXPlosive-Neutralized
XPO	eXPlosive-Optimized
XPP	eXpress Paid Post
XPP	eXtreme Processor Platform
XPP	X Printing Panel
XPR	eX-PRivileges
XPR	eXtreme Programming Refactored
XPS	Transmit [!] Packet Steering
XPS	X-ray Photoelectron Spectroscopy
XPS	XML Paper Specification
XPS	[Informix] eXtended Parallel Server
XPU	X-band Pulse Unit
XPW	eXtreme Pro Wrestling
XPX	eXecutive Physical eXamination
XQA	XML Query Algebra
XQB	eX-QuarterBack
XQC	X-Ray Quantum Calorimeter
XQD	eXperimental Quality Determination
XQE	XQuery Engine
XQF	eXpress Quick Form
XQH	eXcess Quantity Holdover
XQI	XML Query Interface
XQJ	XQuery for Java
XQK	eXpansion of Quadratic Kernal
XQL	XML Query Language
XQM	Xmail Queue Manager
XQN	XML Qualified Name
XQO	XML Query Operation
XQP	eXtended QIO Processor
XQR	eXtended Query Record
XQS	eXperimental Query System
XQV	eXtra-Quiet Vehicle
XRA	X-Ray Analysis
XRB	X-Ray Background
XRC	eXtended Remote Collaboration
XRC	[IBM] eXtended Remote Copy
XRD	X-Ray Diffraction
XRE	X-Ray Event
XRF	eXtended Recovery Facility
XRF	X-Ray Fluorescence [spectrometry]
XRG	eXperimental Reentry Glider
XRH	X-Ray Hazard
XRI	eXtensible Resource Identifier
XRI	X-Ray Image
XRJ	eXtreme Rain Jacket
XRL	eXtended Range Lance
XRM	X Resource Manager
XRM	X-Ray Microanalyser
XRO	X-Ray Optics
XRP	X-Ray Photon
XRR	X-Ray Reflectometer
XRS	X-Ray Spectrometer
XRT	eXtensions for Real-Time
XRT	X-Ray Telescope
XRU	X-Ray Unit
XRV	X-Ray Vector
XRW	X-Ray Warming
XRX	X-Ray eXperiment
XRZ	eXtension of Reconnaissance Zone
XSA	Xen Security Advisory
XSA	XML Software Autoupdate
XSC	eXtensions for Scientific Computation
XSD	eXtra Space Design
XSD	XML Schema Definition [Language]
XSE	Xray Scattering Energy
XSF	X Strike Force
XSF	Xavier Science Foundation
XSG	eXperimental Scout-Great Lakes
XSI	X/Open System Interface
XSI	Xray Shielding and Insulation
XSJ	eX-Society of Jesus
XSK	Xilinx Student Kit
XSL	eXtensible Stylesheet Language
XSM	X Session Manager
XSM	Xray Stress Management
XSN	Xtended Stay Network
XSO	eXcess Speed Observed
XSP	Xylem Sap Potential
XSQ	eXtreme Spreadsheet Quality
XSR	aXway Secure Relay
XSR	eXperimental Sports Roadster
XSS	Cross-Site Scripting [!]
XSS	eXperimental Space Station
XSS	[IBM] XML Security Suite
XST	Cross-Site Tracing [!]
XSU	X-band Satellite Unit
XSU	[Oracle] XML SQL Utility
XSW	X-band antenna SWitch
XSY	eXtended School Year
XTA	eXperimental Trainer-Air Cooled
XTB	eXperimental Torpedo Boeing Aircraft
XTC	eXternal Transmit Clock
XTC	eXtreme Tuesday Club
XTD	XML Type Definition
XTE	Cross-Track Error [!]
XTF	eXtensible Test Framework
XTG	eXternal Transmission Gearing
XTH	Xenon-Tungsten-Halogen
XTI	X-open Transport Interface
XTI	X/Open Transport Interface
XTM	X-ray Tomographic Microscopy
XTO	X-band Triode Oscillator
XTP	eXpress Transfer Protocol
XTP	Xpress Transfer Protocol
XTQ	eXTraction from QuarkXpress
XTR	Xray Transition Radiation
XTS	Cross-Tell Simulator [!]
XTT	Xoops Time Tracker
XTU	Xing Tai University
XTV	eXeter TeleVision
XTW	X-band Traveling Wave
XTX	eXtreme Tactical eXecutioners
XUA	Xtreme Universal Alliance
XUC	eXtended Use Case
XUD	eXcess Usage Data
XUE	eX-Union Executive
XUG	Xbox Users Group
XUH	eX-University of Hertfordshire
XUI	X User Interface
XUI	X-Windows User Interface
XUK	eXperience United Kingdom
XUL	eXtensible User Interface Language
XUL	XML-based User-interface Language
XUM	X-ray Ultra-Microscope
XUO	Xtreme Ultima Online
XUP	eXtreme Unified Process
XUP	Xilinx University Program
XUS	eX United States
XUT	eXtraction Universal Tripod
XUU	Xavier University Union
XUV	eXpendable Unmanned Vehicle
XUV	eXtreme UltraViolet
XUW	Xavier University Women
XUX	Xavier University eXchange
XUY	eXperience UruguaY
XUZ	Transmit User Zero [!]
XVA	eXtra-Vehicular Activity
XVB	Xtreme Volley Ball
XVC	eXtra Video Card
XVD	eXtraordinary Video Disc
XVF	eXtended Vertical File
XVH	eXternal Vacuum Housing
XVJ	eXtra-credit Vocal Jazz
XVL	eXperimental Vertical Liftoff
XVM	eXtreme Volt Modulation
XVN	eXternal Vendor Network
XVO	eXtra Virgin Olive-oil
XVP	Xtremely Violent Posse
XVR	eXchange Voltage Regulator
XVS	eXchange Voltage Signal
XVT	eXecutive Vector Table
XVT	eXtensible Virtual Toolkit
XVV	X-axis towards Velocity Vector
XVW	Xernet Variable Word
XVX	eXpanded Value eXperiments
XVZ	eXcessive Voltage-Zener
XWA	eXtra-Wide Aperture
XWB	Xerox Wireless Broadband
XWC	eXpanded Water Column
XWD	X-Window Dump
XWE	X-treme Wrestling Entertainment
XWF	Xtreme Wrestling Federation
XWG	eXperimental Working Group
XWH	Class X Wheat Hopper
XWI	Xtensa Wrapper Interface
XWL	eXtreme Water Level
XWM	X-Window Manager
XWO	Xtreme Wrestling Order
XWP	Xena the Warrior Princess
XWR	eXtra Water Resistance
XWS	eXtended Workflow Support
XWV	Christian World View [!]
XWZ	Xsetup WiZard
XXA	Xross-Xultural Architecture
XXC	eXpert Cross-Country [!]
XXD	eXtra-eXtra Distance
XXE	XML eXternal Entity
XXE	XMLmind XML Editor
XXF	eXtra-eXtra Fine
XXG	eXtra-eXtra Grande
XXH	eXtra eXtra Heavy
XXL	eXtra eXtra Large
XXP	Xbase and eXchange Platform
XXS	eXtra eXtra Small
XXT	eXtra eXtra Tough
XXW	eXtra eXtra Wide
XXX	Xperience Xtreme Xcitement
XXX	Xtremely Xcruciating Xperience
XYA	Cross Your Arms [!]
XYI	XYlose Isomerase
XYM	eXamine Your Mind
XYT	eXpanding Youth Trends
XYU	eXamine Your Underwear
XYY	eXchange of Yiddish Youth
XYZ	eXamine Your Zipper
XZB	eXtreme Zone Boundary
XZE	eXtreme Zone Effect
XZI	eXpansion Zone Index
XZM	eXterior Zone Melting
XZP	eXtended Zinc Process
XZW	Xtreme Zone Wrestling