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tropical cyclone vs. tropical storm

tropical cyclone
[trop-i-kuhl sahy-klohn] / ˈtrɒp ɪ kəl ˈsaɪ kloʊn /

noun

Meteorology.

  1. a warm-core cyclone that originates over a tropical ocean area, generally beginning as a tropical depression and having the potential to intensify and develop into a hurricane or typhoon, classifications that depend on where the storm is occurring.

tropical storm

noun

Meteorology.
tropical storms plural

  1. a tropical cyclone of less than hurricane force.