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Not Cisco official, but a hub is very generally a center of multiple spokes, term often used for a L2 multi-port Ethernet repeater.
A bridge is generally a L2 device that applies some intelligence to traffic forwarding. It controls replication of ingress traffic to egress and/or it might do media conversion.
A switch generally is a multi-port L2 bridge without media conversion.
A router is basically the L3 version of a bridge although there's always a L3 forwarding decision (unless device is configured for L2 bridging).
In the Cisco line-up, term usage can be confusing. For instance, a 7600 and a 6500 if exactly the same hardware (except "chassis") and if running exactly the same IOS (before they were split into different IOS trains), labels the 7600 a router and the 6500 a switch. (NB: to be fair, the 7600 and 6500 each supports/supported hardware and software features unique to their router/switch roles, although probably this was a marketing decision, not a technical decision.)
PS:
And don't forget MLS or MPLS which "blur" the distinction between L2 bridges and L3 routers.
