barometer

UK: bəˈrɒmɪtə | US: bəˈrɑːmɪtər

Definition
  1. n. an instrument measuring atmospheric pressure, used in weather forecasting

  2. n. (figurative) something that reflects or indicates changes in conditions or opinions

Structure
baro <weight/pressure>meter <measure>
Etymology

The word "barometer" combines Greek roots: "baros" (βάρος, meaning "weight" or "pressure") and "metron" (μέτρον, meaning "measure"). Invented in the 17th century by Evangelista Torricelli, the device literally "measures atmospheric pressure," reflecting its scientific purpose. Over time, it also gained metaphorical use to describe indicators of societal or environmental shifts.

Examples
  1. The barometer fell sharply, signaling an approaching storm.

  2. Economists view consumer confidence as a barometer of financial health.

  3. She adjusted the barometer to ensure accurate readings.

  4. His mood swings acted like a barometer for the team’s morale.

  5. Ancient sailors relied on barometers to predict weather changes.