A flail is an agricultural tool used for threshing, the process of separating grains from their husks.

It is usually made from two or more large sticks attached by a short chain; one stick is held and swung, causing the other (the swipple) to strike a pile of grain, loosening the husks. The precise dimensions and shape of flails were determined by generations of farmers to suit the particular grain they were harvesting.

Flails have generally fallen into disuse in many nations because of the availability of technologies such as combine harvesters that require much less manual labour. But in many places, such as Minnesota, wild rice can only be harvested legally using manual means, specifically through the use of a canoe and a flail.

In ancient Egypt the flail was a symbol associated with the monarch, symbolizing his ability to provide for the people.

More Info: en.wikipedia.org