1. Being in effect or operation
   "bus service is in operation during the emergency"
   - operational, operating

See also: operative

• wrothful
• wrought
• wrought iron
• wrought-up
• wrt
• wry
• wry face
• wryly
• wrymouth
• wryneck
• wryness
• WSW
• WTC
• WTO
• WTV
• Wu
• Wu dialect
• Wuerzburg
• Wuhan
• wulfenite
• Wulfila
• wunderkind
• Wurlitzer
• wurst
• wurtzite