windmill

A windmill is a structure which redirects energy from wind-powered blades into mechanical energy for use on the same site or nearby. Pumping water is one application of a windmill. This does not include the activity of wind turbines, which convert wind power into electricity.

The rotating blades drive work through a mechanical connection. Pumping water is one such task; the machinery uses the motion without first converting it to electricity.

A wind turbine driving an electrical generator has a different output. The windmill distinction concerns the direct mechanical use of wind power, rather than whether its work supports agriculture.