WordWeb Online

1. A mill that is powered by the wind
    
2. Generator that extracts usable energy from winds
   - aerogenerator, wind generator
    
3. [Brit] A toy consisting of vanes of coloured paper or plastic that is pinned to a stick and spins when it is pointed into the wind
   - pinwheel [N. Amer], pinwheel wind collector [N. Amer]

1. Rotate one's arms with a sweeping motion
   "she ran down the hill, windmilling her arms with glee"
    
2. (of a rotating part of a machine) become disengaged and rotate freely
   "The axle broke and the wheel windmilled in place"

Derived forms: windmilled, windmilling, windmills

Type of: generator, grinder, mill, milling machinery, plaything, toy

Encyclopedia: Windmill, Derbyshire