| W | Tungsten (from German Wolfram) - Watt - West | - | Astronomy |
| W/ | With: Software W/Documentation. Typically Used In Advertising Or To Abbreviate Headings. Never Used In Formal Body Text. | - | Astronomy |
| W/O | Without: Software W/o Documentation | - | Astronomy |
| W3C | World Wide Web Consortium | - | Astronomy |
| WA | Namibia (FIPS 10-4 Country Code; From West Africa) - Washington State (postal Symbol) - Western Australia (postal Symbol) | - | Astronomy |
| WA | Walloon Language (ISO 639-1 Code) | - | Astronomy |
| WAAC | Women's Army Auxiliary Corps (WWII UK) | - | Astronomy |
| WAAF | Women's Auxiliary Air Force (WWII UK) | - | Astronomy |
| WAC | Women's Auxiliary Corps (WWII Canada) | - | Astronomy |
| WACC | Weighted Average Cost Of Capital (accounting) | - | Astronomy |
| WACS | What-A-Cartoon! Show | - | Astronomy |
| WAD | Weapons Alert Designator | - | Astronomy |
| WAGS | Wives And Girlfriends (of England National Football Team Players At The 2006 FIFA World Cup) | - | Astronomy |
| WAK | Wake Island (ISO 3166 Trigram | - | Astronomy |
| WAN | Wide Area Network | - | Astronomy |
| WAP | Wireless Application Protocol | - | Astronomy |
| WASP | White Anglo-Saxon Protestant - Wide Angle Search For Planets - Women Airforce Service Pilots | - | Astronomy |
| WASP | Short Form Of WAAAAP (Wind Atlas Analysis And Application Program) | - | Astronomy |
| WAYP | White And Yellow Pages | - | Astronomy |
| WB | Warner Brothers - Welcome Back (Internet Short-hand) | - | Astronomy |
| WB | Weber | - | Astronomy |
| WBE | Work Breakdown Element | - | Astronomy |
| WC | Water Closet - Winston Churchill - World Cup (sports) | - | Astronomy |
| WCBO | World Chess Boxing Organisation | - | Astronomy |
| WCBP | World Centre For Birds Of Prey | - | Astronomy |
| WCL | World Confederation Of Labour | - | Astronomy |
| WCS | Weapon Control Status - Wildlife Conservation Society | - | Astronomy |
| WCW | World Championship Wrestling | - | Astronomy |
| WDC | Western Design Center - World Data Center | - | Astronomy |
| WDWR | Walt Disney World Resort | - | Astronomy |
| WEBS | Weapon Effectiveness Battle Simulation | - | Astronomy |
| WEEE | Waste Electrical And Electronic Equipment | - | Astronomy |
| WEU | Western European Union | - | Astronomy |
| WEZ | Weapon Engagement Zone | - | Astronomy |
| WF | Wallis And Futuna Islands (ISO 3166 Digram) | - | Astronomy |
| WFC | Women's Forage Corps (WWII UK) | - | Astronomy |
| WFD | Weaponof Focused Destruction | - | Astronomy |
| WFF | Wallops Flight Facility | - | Astronomy |
| WFP | World Food Program | - | Astronomy |
| WFZ | Weapons Free Zone | - | Astronomy |
| WG | Working Group - Wade-Giles | - | Astronomy |
| WGS 84 | World Geodetic System 1984 | - | Astronomy |
| WH | Wehrmacht Heer (German WW2 Army Vehicle Licence Plate Code) | - | Astronomy |
| WHAM | Wisconsin Hydrogen-Alpha Mapping (telescope) | - | Astronomy |
| WHI | Women's Health Initiative | - | Astronomy |
| WHO | World Health Organisation | - | Astronomy |
| WHS | (U.S.) Washington Headquarters Services | - | Astronomy |
| WI | Western Sahara (FIPS 10-4 Country Code) - Wisconsin (postal Symbol) | - | Astronomy |
| WIA | Wounded In Action | - | Astronomy |
| WIMP | Weakly Interacting Massive Particle - Windows | - | Astronomy |
| WIN | T -Warfighter Information Network-Tactical | - | Astronomy |
| WIPO | World Intellectual Property Organization | - | Astronomy |
| WIPP | [Nuclear] Waste Isolation Pilot Project | - | Astronomy |
| WIYN | Wisconsin Indiana Yale NOAO Telescope Consortium | - | Astronomy |
| WK | Wake Island (ISO 3166 Digram | - | Astronomy |
| WKYP | Will Keep You Posted | - | Astronomy |
| WL | Wehrmacht Luftwaffe (German WW2 Air Force Vehicle Licence Plate Code) | - | Astronomy |
| WLB | Women's Land Brigade (WWII Canada) | - | Astronomy |
| WLF | Wallis And Futuna Islands (ISO 3166 Trigram) | - | Astronomy |
| WLN | Walloon Language (ISO 639-2 Code) | - | Astronomy |
| WLOG | Without Loss Of Generality (see WOLOG) | - | Astronomy |
| WM | Wehrmacht Marine (German WW2 Navy Vehicle Licence Plate Code) | - | Astronomy |
| WMANUS | West Midlands Area National Union Of Students | - | Astronomy |
| WMD | Weapon[s] Of Mass Destruction - World Movement For Democracy ? | - | Astronomy |
| WMI | Wildlife Management Institute | - | Astronomy |
| WMO | World Meteorological Organization | - | Astronomy |
| WNA | World Nuclear Association | - | Astronomy |
| WNF | Will Not Fix | - | Astronomy |
| WNSD | What's New | - | Astronomy |
| WNW | West North-West | - | Astronomy |
| WO | Warrant Officer | - | Astronomy |
| WO | Wolof Language (ISO 639-1 Code) | - | Astronomy |
| WOL | Wolof Language (ISO 639-2 Code) | - | Astronomy |
| WOLOG (OR WLOG) | WithOut Loss Of Generality | - | Astronomy |
| WOM | Write Only Memory (a Joke From Stan Kelly-Bootle) | - | Astronomy |
| WOS | Wilson Ornithological Society | - | Astronomy |
| WOT | Waste Of Time | - | Astronomy |
| WP | White Phosphorus (ammunition) | - | Astronomy |
| WPB | War Production Board During World War II | - | Astronomy |
| WPE | World Pork Expo | - | Astronomy |
| WPK | Wider Peacekeeping | - | Astronomy |
| WR | Wide Receiver (football) | - | Astronomy |
| WRAC | Women's Royal Army Corps (WWII UK) | - | Astronomy |
| WRAIR | Walter Reed Army Institute Of Research | - | Astronomy |
| WRBWWRM | We Read Best What We Read Most | - | Astronomy |
| WRC | World Rally Championship | - | Astronomy |
| WRNS | Women's Royal Naval Service (WWII UK) (pronounced Wrens) | - | Astronomy |
| WRS | Worldwide Reference System | - | Astronomy |
| WRT | With Respect To | - | Astronomy |
| WRT | Writer Response Theory | - | Astronomy |
| WRT | World Rally Team | - | Astronomy |
| WRT OR W/R/T | With Respect To Or With Regard To | - | Astronomy |
| WRVS | Women's Royal Voluntary Service | - | Astronomy |
| WS | Samoa (ISO 3166 And FIPS 10-4 Country Code Digram; From West Samoa) -Writer To The Signet (a Scottish Solicitor) | - | Astronomy |
| WSC | Weapon System Catalogue | - | Astronomy |
| WSDL | Web Services Description Language | - | Astronomy |
| WSJ | Wall Street Journal | - | Astronomy |
| WSM | Samoa (ISO 3166 Trigram; From West Samoa) | - | Astronomy |
| WSMR | White Sands Missile Range (whiz-murr) | - | Astronomy |
| WST | Water Soluble Tetrazolium (assay) -Samoan Tala (ISO 4217 Currency Code) | - | Astronomy |
