Switch
The long tuft of hair at the end of a cow's tail, used to brush away flies.
Also: tail switch, tail brush
The switch is the brush of long hair at the end of a cow's tail. Cattle swing it to keep flies and biting insects off their backs and flanks, and animals standing side by side, head to tail, keep flies off each other's faces. The switch keeps growing, and on show cattle it is washed and combed out to look full. Colour can be part of a breed's description: the Gloucester, for example, has a white tail along with a white line down its back. Yak tails have long been made into fly whisks, the chamara or chowrie waved over deities and rulers in South Asian temples and courts.