Textbook defines coupling capacitor

[asdf1]

textbook defines "coupling capacitor"

just curious...
my textbook defines "coupling capacitor" as "ideally appears as an open to dc and as a short to ac."
but what does that have to do with "couple" in the english sense?
i'm not an electronics major, but I'm taking a course in electric circuits, so i don't know if that term has some special meaning in ee?

 

[Astronuc]

Coupling with respect to capacitor or inductor refers to coupling/connect one circuit to another, so that the output (voltage/current) of one circuit is the input of the other circuit.

In a transformer, the coils in one arm (inductor) induce a voltage/current in another coil (inductor) attached to the same magnetic circuit by virtue of a time varying (usually AC) current.

An single inductor connected passes both DC and AC

A capacitor passes AC, but not DC.

 

[asdf1]

thank you very much! :)