The best of the best. When something's not quite up to standard, 'bunnamagoo' may be used in comparison to make an example of just how bad that something is - be it a person, a car, the weather, or a delicate wine.

May be used as a noun or as an adjective.
"This wine is good, but it's no bunnamagoo!"

-or-

"You're looking very bunnamagoo this evening."
by WACKADOO! October 24, 2011
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