English to English
1. the central part of a car wheel (or fan or propeller etc) through which the shaft or axle passes
2. 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
3. The central part, usually cylindrical, of a wheel; the nave. See Illust. of Axle box.