A bellwether's any entity in a given arena that serves to create or influence trends or to presage future happenings. The term's derived from the Middle English bellewether and refers to the practice of placing a bell around the neck of a castrated ram (a wether) leading its flock of sheep. The movements of the flock could be noted by hearing the bell before the flock was in sight. Politics In politics, the term's more often applied in the passive sense to describe a geographic region where po… (More on Bellweather)