From Longman Dictionary of Contemporary Englishbarometerba‧rom‧e‧ter /bəˈrɒmɪtə $ -ˈrɑːmɪtər/ noun [countable] 1 
TMHEMan instrument that measures changes in the air pressure and the weather, or that calculates height above sea level2 TMSHOW/BE A SIGN OFsomething that shows any changes that are happening in a particular situation The skin is an accurate barometer of emotional and physical health. —barometric /ˌbærəˈmetrɪk◂/ adjective [only before noun] —barometrically /-kli/ adverb
TMHEMan instrument that measures changes in the air pressure and the weather, or that calculates height above sea level2 TMSHOW/BE A SIGN OFsomething that shows any changes that are happening in a particular situation The skin is an accurate barometer of emotional and physical health. —barometric /ˌbærəˈmetrɪk◂/ adjective [only before noun] —barometrically /-kli/ adverbExamples from the Corpus
barometer• Applications for building permits are a barometer of future construction activity.• Viewed as a barometer of interest-rate expectations, shorter-term notes, were mixed.• Royal portraiture appears to be a barometer of the state of the art.• But if the past is any barometer, her image may shift with the issues of the moment.• That energy barometer naturally comes down at this stage of life.• Do you know, when you were little, darling, I used to think of you as the family barometer.• Wading birds, the barometer of any marsh's health, have been devastated.• The barometer was down to twenty eight.From Longman Business Dictionarybarometerba‧rom‧e‧ter /bəˈrɒmɪtə-ˈrɑːmɪtər/ noun [countable] ECONOMICS if something is a barometer of the economy, it gives important information about the condition of the economy as a wholeThe growth in demand for electricity is one of the most accurate barometers of the economy. → see also indicatorOrigin barometer (1600-1700) Greek baros “weight, pressure” + English -meter 