We have never been told what the ECHO acronym means, right?

Question

We have never been told what the ECHO acronym means, right?

In the first game, Claptrap calls it (1, 2):

... ECHO communication device and heads-up display ...

So, it could be recursive...

ECHO Communicator and Heads-up Overlay

or something.

But we don't know, right?

Answer 1

Not in game, but it has been hinted at that it stands for Each Citizen Has One. You cannot start the game without it, and everyone seems to have them and leaves recordings everywhere. That's just conjecture though.