"A wind vane, weather vane, or weathercock is an instrument used for showing the direction of the wind. It is typically used as an architectural ornament to the highest point of a building. The word vane comes from the Old English word fana, meaning "flag".
Although partly functional, wind vanes are generally decorative, often featuring the traditional cockerel design with letters indicating the points of the compass. Other common motifs include ships, arrows, and horses. Not all wind vanes have pointers. When the wind is sufficiently strong, the head of the arrow or cockerel (or equivalent depending on the chosen design) will indicate the direction from which the wind is blowing." - (en.wikipedia.org 24.12.2021)
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