1.) When something is of or has the characteristics of a situation wherein a person might be caused to use the word "damn".
2.) Exactly like 'damn' and can be used accordingly.
darB: I was double-charged for a tank of gas, and my bank denied my dispute.
derF: Damnage. I'd be pissed.
darB: Apparently the email I wrote when I got the letter was pretty good, though. I ended up getting a phone call from someone in executive escalations. They fixed it, but I'm still changing banks. You don't mess with my money.