tropical depression

[trop-i-kuhl di-presh-uhn]

noun

Meteorology.

1. an atmospheric low-pressure system originating in the tropics, specifically, a tropical cyclone in which the maximum sustained wind speed is 38 miles per hour (62 kilometers per hour) or less.

tropical depression

noun

1. an area of heavy rains and winds, the first stage in the development of a possible hurricane

tropical depression

1. A tropical cyclone having sustained surface winds less than 39 mi (63 km) per hour.

2. See Note at cyclone

Word History and Origins

Origin of tropical depression¹

First recorded in 1845–50; tropical + depression (in the sense “low atmospheric pressure”