Definition - What does Watt mean?
Watt (W) is the common unit of electrical energy used in the United States. A watt is defined as a joule (unit of energy) per second and is the common standard for analysis of power consumption in U.S. residential or business systems, or in any other kind of electrical setup.
Techopedia explains Watt
In the United States, residential energy systems are typically evaluated in terms of "kilowatt hours." Customers are billed in terms of kilowatt hours, which is the unit of measurement for a power use of 1000 W for the time frame of 1 hour. Converting watts or kilowatts into watt hours or kilowatt hours involves looking at the static use of a certain appliance with a given wattage. For example, ten 100-W light bulbs used consecutively for 1 hour will generate 1 kWh of collective use.
As with data use, larger and larger units of measurement apply to the collective analysis of electrical systems. In addition to the kilowatt, which represents 1000 W, terms like megawatt, gigawatt and terawatt are used for metering much larger amounts of electricity.