Nyoink. Does that classify as an onomatopoeic word?

One of the guys at a party I was at on Friday kept saying it. The party was the farewell for an really close friend who's going to be overseas for a long, long time. I'm going to miss her terribly, and can't see any way for being able to visit any time in the next four years while I'm having a go at the whole uni thing. I'll have to settle for seeing her if/when she comes back to Sydney to visit.