Home›Browse›W›watt-secondwatt-secondOur editors are putting together more complete content — check back in about 20 minuteswatt-secondwatt-second — nounnoun1. a unit of energy equal to one watt of power for one second1.nounDefinitiona unit of energy equal to one watt of power for one secondExampleThe LED light consumed 3600 watt-seconds of energy in one hour.