cyclone

Concise Oxford English Dictionary © 2008 Oxford University Press:
cyclone /ˈsʌɪkləʊn/

▶noun

• 1 Meteorology a system of winds rotating inwards to an area of low barometric pressure; a depression.

• 2 a tropical storm.

– derivatives
cyclonic adjective,
cyclonically adverb.

– origin C19: prob. from Gk kuklōma ‘wheel, coil of a snake’.