<P> A weather vane, wind vane, or weathercock is an instrument 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". </P> <P> Although partly functional, weather 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 weather 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 . </P>

Tool shaped like an arrow that indicates wind direction