- WAF
- Water Accumulated Fraction
- WAFI
- Wax Anti Settling Flow Improver
- WASA
- Wax Anti Settling Additive
- WCM
- Wax Crystal Modifier
- WDFQS
- Winter Diesel Fuel Quality Survey
- WFD
- Waste Framework Directive
- WHDC
- World Harmonized Drive Cycle
- WLTP
- Worldwide Harmonized Light Vehicles Test Procedures
- WOE
- Weight of Evidence
- WOT
- Wide Open Throttle
- WOTAG
- Waste Oil Technical Advisory Group (UK)
- WTD
- Weighted Total Demerits (of engine test ratings)
- WTI
- West Texas Intermediate
