Word of the Day:

: one that takes the lead or initiative : leader; also : an indicator of trends

The company has long been viewed as a bellwether for the tech market, so analysts are watching it closely.

"Plus, on an increasingly divided council, and in a new district elections system inviting wholesale change, Godden's race could be a bellwether for how incumbents are faring this election year." - Heidi Groover, The Stranger, May 13, 2015

More example sentences

We usually think of sheep more as followers than leaders, but in a flock one sheep must lead the way. Long ago, it was common practice for shepherds to hang a bell around the neck of one sheep in their flock, thereby designating it the lead sheep. This animal was called the bellwether, a word formed by a combination of the Middle English words belle (meaning "bell") and wether (a noun that refers to a male sheep that has been castrated). It eventually followed that bellwether would come to refer to someone who takes initiative or who actively establishes a trend that is taken up by others. This usage first appeared in English in the 13th century.