The act of distracting another while they are hard at work or trying to concentrate on some very important task (writing, surgery, bomb disposal etc).
"Cheers for that goatsnab. I nearly blew up the reactor."

Or go up behind a friend when they are hard at work, preferrably at a time when they definitely do not want to be distracted, grab their shoulders and push down repeatedly (they should be sitting on a partially sprung chair, ideally), while saying 'Goatsnab, goatsnab, goatsnab!'
by Bellser July 29, 2006
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