A "something" on which to blame farts.
Rather than accept blame for farting(noisily), one exclaims that they had witnessed a creature in close proximity by invoking it's name and looking behind.

Interchangeable with local fauna.
FFRRRTTTTT...
"OH! Darn Rocky Mountain Barking Spiders sneaking up on me again."
by Psykram May 12, 2010
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