funnel cloud

noun

a rapidly rotating funnel-shaped cloud extending downward from the base of a cumulonimbus cloud, which, if it touches the surface of the earth, is a tornado or waterspout.

Also called pendant cloud, tornado cloud, tuba.

Examples from the web for funnel cloud

Water droplets from the mesocyclone's moist air form a funnel cloud.
The mesocyclone can eventually form a stormy funnel cloud, which becomes a tornado when it touches down.
If a cold air funnel is spotted, take the same precautions you would for any funnel cloud or tornado.
They can appear without warning and be invisible until dust and debris are picked up or a funnel cloud appears.
Tornadoes are storms with rapidly rotating winds that form a funnel cloud.
The first image shows the funnel cloud, while the next two show the tornado.
They can appear suddenly without warning and can be invisible until dust and debris are picked up or a funnel cloud appears.
The disaster warning system will be activated when a tornado or funnel cloud is reported.

British Dictionary definitions for funnel cloud

funnel cloud

noun

a whirling column of cloud extending downwards from the base of a cumulonimbus cloud: part of a waterspout or tornado

Contemporary definitions for funnel cloud

noun

a funnel-shaped cloud descending from a towering cumulus or cumulonimbus that, if it reaches the ground, becomes a tornado

Usage Note

science