"hub" in the noun sense
1. hub
the central part of a car wheel (or fan or propeller etc) through which the shaft or axle passes
2. hub
a center of activity or interest or commerce or transportation a focal point around which events revolve
"the playground is the hub of parental supervision"
"the airport is the economic hub of the area"
Source: WordNet® (An amazing lexical database of English)
Princeton University "About WordNet®."
WordNet®. Princeton University. 2010.
View WordNet® License