Weathervane or Weather vane?
Weathervane
Exemple : ‘’The weathervane showed the wind was blowing from the east.’’
The noun "weathervane" can be spelt either as a single word or in the opinion of some it can be written as two separate words. There is, however, some controversy over this: the single-word spelling is universally accepted however and therefore it is best to stick with this. The word refers to the device placed on top of buildings which shows where the wind is blowing from.