# List of acronyms: X

This list contains acronyms, initialisms, and pseudo-blends that begin with the letter X.
For the purposes of this list:
* acronym = an abbreviation pronounced as if it were a word, e.g., SARS = severe acute respiratory syndrome, pronounced to rhyme with cars
* initialism = an abbreviation pronounced wholly or partly using the names of its constituent letters, e.g., CD = compact disc, pronounced cee dee
* pseudo-blend = an abbreviation whose extra or omitted letters mean that it cannot stand as a true acronym, initialism, or portmanteau (a word formed by combining two or more words).
    (a) = acronym, e.g.: SARS – (a) severe acute respiratory syndrome
    (i) = initialism, e.g.: CD – (i) compact disc
    (p) = pseudo-blend, e.g.: UNIFEM – (p) United Nations Development Fund for Women
    (s) = symbol (none of the above, representing and pronounced as something else; for example: MHz – megahertz)
Some terms are spoken as either acronym or initialism, e.g., VoIP, pronounced both as voyp and V-O-I-P.
(Main list of acronyms)

## Contents

* Top
* X0–9 XA XB XC XD XE XF XG XH XI XJ XK XL XM XN XO XP XQ XR XS XT XU XV XW XX XY XZ

## XA

* XAF – (s) BEAC (Banque des états de l'Afrique centrale) Central Africa CFA (Coopération financière en Afrique centrale) franc (ISO 4217 currency code)
* XAG – (s) Silver Troy ounce (ISO 4217 currency code)
* XAU – (s) Gold Troy ounce (ISO 4217 currency code)

## XB

* XBA – (s) European Composite Unit (EURCO; Bonds market unit) (ISO 4217 currency code)
* XBB – (s) European Monetary Unit (E.M.U.; Bonds market unit) (ISO 4217 currency code)
* XBML – (p) eXtended Business Modelling Language

## XC

* XC – (s) Ninety (in Roman numerals)
* XCBL – (i) XML Common Business Library
* XCD – (s) East Caribbean dollar (ISO 4217 currency code)

## XD

* XD – Used in chatrooms or email for smiley face. X is the eyes; squinted D is the mouth; XD.

## XE

* Xe – (s) Xenon

## XF

* XF
** (s) Automobile made by Jaguar
** (s) Truck made by DAF Trucks
** (p) IATA code for Vladivostok Air
* XFA – (i) XML Forms Architecture
* XFC – (i) Xtreme Fighting Championships
* XFD – (s) Fighter aircraft made by Douglas
* Xfe – (i) X File Explorer
* XFF – (i) X-Forwarded-For
* XFG – (p) Exfoliation glaucoma
* XFH
** (s) 1932 prototype U.S. Navy fighter aircraft made by Hall
** (i) X-ray fluorescence holography
* XFN
** (i) XHTML Friends Network
** (p) IATA code for Xiangyang Liuji Airport
* XFR – (s) Automobile made by Jaguar
* XFT – (p) X FreeType interface library
* XFW – (p) IATA code for Hamburg Finkenwerder Airport

## XG

* XG – (s) Automobile made by Hyundai
* XGA – (p) Extended Graphics Array
* XGE
** (i) Xoreax Grid Engine
** (s) Signal for "I Surrender"
* XGG – (p) IATA code for Gorom Gorom Airport
* XGN – (p) IATA code for Xangongo Airport
* XGP – (p) Extreme Game Player
* XGR – (p) IATA code for Kangiqsualujjuag (Georges River) Airport

## XH

* xh – (s) Xhosa language (ISO 639-1 code)
* xho – (s) Xhosa language (ISO 639-2 code)
* XHTML – (p) eXtensible Hypertext Markup Language
* XHR – (p) eXtra high Image resolution – XMLHTTPRequest

## XI

* XI – (s) Eleven (in Roman numerals)
* XII – (s) Twelve (in Roman numerals)
* XIII – (s) Thirteen (in Roman numerals)
* XIV – (s) Fourteen (in Roman numerals)
* XIX – (s) Nineteen (in Roman numerals)

## XJ

* XJ
** (s) Automobile made by Jaguar
** (s) Automobile made by Jeep
* XJL
** (s) Amphibian aircraft made by Columbia
** (s) Automobile made by Jaguar
* XJS – (s) Automobile made by Jaguar

## XK

* XK
** (s) Automobile made by Jaguar
** (s) Automobile made by Jeep
** (s) Kell blood group precursor
* XKA – (p) IATA code for Kantchari Airport
* XKB – (p) X keyboard extension
* XKE – (s) Automobile made by Jaguar
* XKH – (p) IATA code for Xieng Khouang Airport
* XKR – (s) Automobile made by Jaguar
* XKS – (p) IATA code for Kasabonika Airport
* XKY – (p) IATA code for Kaya Airport

## XL

* XL
** (p) eXtra Large
** (s) Forty (in Roman numerals)

## XM

* XML – (p) eXtensible Markup Language
* XMSF – (p) eXtensible Modelling and Simulation Framework

## XN

* XN – (s) Christian – (s) Nordic Patent Institute
* XNA
** (p) IATA code for Northwest Arkansas Regional Airport
** (i) X-No-Archive
** (i) Xeno Nucleic Acid
* XNC – (i) X Northern Captain
* XNN – (p) IATA code for Xining Caojiabao Airport
* XNS
** (i) Xerox Network Systems
** (p) Extensible Name Service
** (s) Christians
* XNU – (p) X is Not Unix

## XO

* XO
** (i) Χριστιανός Ορθόδοξος (Xristianos Orthodoksos, Greek for "Eastern Orthodoxy")
** (p) eXecutive Officer
** eXtra Old (brandy grade)
* XOF – (s) BCÉAO (Banque centrale des états de l'Afrique de l'Ouest) West African CFA (Communauté financière d'Afrique) franc (ISO 4217 currency code)

## XP

* XP – (p) eXperience Point (role-playing games)
* XPD – (s) Palladium Troy ounce (ISO 4217 currency code)
* XPF – (s) CFP franc (ISO 4217 currency code)
* XPT – (s) Platinum Troy ounce (ISO 4217 currency code)

## XQ

* XQJ – (p) XQuery API for Java™
* XQP – (p) IATA code for Quepos La Managua Airport
* XQU – (p) IATA code for Qualicum Beach Airport

## XR

* XRML – (p) eXtensible Rights Markup Language
* XRP – (s) a cryptocurrency

## XS

* XS – (i) Xiaolin Showdown -(s) Extra Small
* XSL – (p) eXtensible Style Language

## XT

* XTMH – eXtreme Technology Multiprocessor Hyperlanguage

## XU

* XUL – (p) XML User Interface Language

## XV

* XV – (s) Fifteen (in Roman numerals)
* XVA – an X-Value Adjustment (in finance)
* XVI – (s) Sixteen (in Roman numerals)
* XVII – (s) Seventeen (in Roman numerals)
* XVIII – (s) Eighteen (in Roman numerals)

## XW

* XWB – (p) (Airbus A350) "Extra Wide Body"
* XWF – (i) Xcitement Wrestling Federation
* XWM – (i) X window manager
* XWN – (p) eXtended WordNet
* XWS – (i) X Window System

## XX

* XX – (s) Twenty (in Roman numerals)
* XXX – (s) Hardcore pornography (film rating) – Thirty (
* in Roman numerals)

## XY

* XYA – (p) IATA code for Yandina Airport
* Xyl – (s) Xylobium

## XZ

* XZA – (p) IATA code for Zabré Airport
* XZN – (s) Triple square screw driver