hub

Concise Oxford English Dictionary © 2008 Oxford University Press:
hub/hʌb/

▶noun

• 1 the central part of a wheel, rotating on or with the axle, and from which the spokes radiate.

• 2 the centre of an activity, region, or network.

– origin C16 (denoting a shelf at the side of a fireplace for heating pans): of unknown origin (cf. hob1).