One thousand million (10⁹) watts, an amount of power large enough to power such things as a midsize town or several small ones. (Consuming 1 gigawatt during a duration of 1 hour consumes 1 gigawatt-hour of energy.)
In the 2020s, the race for AI data centers has Big Tech searching for ways to add multiple gigawatts of additional grid capacity to a regional power grid.
In a famous movie about time travel, the mad scientist tells the teenage hero that the time machine requires 1.21 gigawatts of power to operate.
(metonymic) The amount of data center capacity or amount of compute that this amount of power can provide under the current technological state of the art (PUE, clock speed, etc).