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Connection 101, not for the uninitiated...

Anything that connects to another something is a connector. To a certain desirable extent it can be an isolator, too, but is a connector.

Which property practically prevails depends on multitude of factors, but isolators mentioned earlier are connectors.

In the link above, as removed from pertinence about audio reproduction as it is, there are two moments that emphasize limits of isolation.

At around 2:45, word "relatively" and at around 6:45 "bonding them" ("connecting them", one could say).

In fact, there is much more later in the video, but those two are enough for aspiring novices.