hub
/hʌb/noun
1- the central part of a wheel, rotating on or with the axle, and from which the spokes radiate毂。
1.1
- a place or thing which forms the effective centre of an activity, region, or network（活动、地区或网络的）中心：
the kitchen was the hub of family life.
厨房是家庭生活的中心。
短语
hub-and-spoke
- denoting a system of air transportation in which local airports offer flights to a central airport where international or long-distance flights are available（空中交通）辐射状的。
词源
early 16th cent. (denoting a shelf at the side of a fireplace used for heating pans)： of unknown origin （compare with HOB1）.