barometer

1. (figurative, by extension) Anything used as a gauge or indicator.Examples: ""An election is not necessarily an accurate barometer of public opinion. There are other ways in which it makes itself felt, through the press, the forum, discussion, and through every other type of communication.""; "The weakest members of society become social barometers or canaries in a coal mine."; "Italy’s 10-year yield spread versus Germany, considered a barometer of political and economic risks in the euro area, climbed as high as 1.9 percentage points on Tuesday, its widest since the early stages of the pandemic when investors dumped riskier eurozone government debt."broadlyfiguratively