On Mon, 2008-04-14 at 18:04, Arvid Ephraim Picciani wrote:
> Hi,
> I'd like to discuss if returning a mail that went through a mailing list, back
> to the sender can be described as backscatter.

I would say not.

"Backscatter" to me means 550 rejects that are sent to a bystander
because the sending address was forged by some spamming low-life.