The definition of a bellwether is someone or something that is an indicator of future trends.
(noun)If rising unemployment numbers are an indicator of a recession, then they are an example of a bellwether of recession.
See bellwether in Webster's New World College Dictionary
noun
Origin: ME: see bell & wether
See bellwether in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English bellewether, wether with a bell hung from its neck, leader of the flock
Origin: : belle, bell; see bell1
Origin: + wether, wether; see wether
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