Weathervane (noun)

A device mounted on a rooftop or other high place that indicates the direction of the wind.

Origin:

From middle english weverfane, from wever ("weather") + fane ("flag"), from old english wæfre ("wavering, unstable") + fana ("flag, banne.r")

Examples:

1. The weathervane on top of the church steeple pointed towards the north.
2. The old weathervane had been replaced with a new one that was more accurate.
3. The weathervane was a rooster, which was a common symbol for a rural area.
4. He climbed to the top of the building to fix the weathervane that had been bent by the wind.
5. The weathervane was an important tool for sailors and farmers to predict the weather.