vortex

Concise Oxford English Dictionary © 2008 Oxford University Press:
vortex /ˈvɔːtɛks/

▶noun (pl. vortexes or vortices /-tɪsiːz/) a whirling mass, especially a whirlpool or whirlwind.

– derivatives
vortical adjective,
vortically adverb,
vorticity /vɔːˈtɪsɪti/ noun,
vorticose adjective,
vorticular /vɔːˈtɪkjʊlə/ adjective.

– origin C17: from L. vortex, vortic-, lit. ‘eddy’, var. of vertex.