"funnel cloud." YourDictionary, n.d. Web. 11 October 2018. <http://www.yourdictionary.com/funnel-cloud>.
funnel cloud. (n.d.). Retrieved October 11th, 2018, from http://www.yourdictionary.com/funnel-cloud
A funnel-shaped cloud descending from a larger cloud, especially from a wall cloud, caused by the sudden condensation of water in the extreme low pressure of rapidly rotating air, as typically occurs in a tornado.