WAAS
Wide Area Augmentation System
WD/WINDR
Wind Direction
WHO
World Health Organisation
WMA
WXR Waveguide Adapter
WMI
WXR Indicator Mount
WMS
Wide area Master Station
WMSC
Weather Message Switching Center
WMSCR
Weather Message Switching Center Replacement
WOFW
Weight-off-Wheels, indicates aircraft is off ground since lift off
WONW
Weight-on-Wheels, indicates aircraft is on ground since touch down
WPT
Waypoint
WRT
WXR Receiver Transmitter
WTO
World Tourism Organisation
WTO-OMC
World Trade Organisation (formerly GATT)
WTTC
World Travel and Tourism Council
WX
Weather
WXR
Weather Radar System
WYPT
Waypoint