Speaking without thought; talking like an un-educated person on a subject they know nothing about; giving an answer to a question that has no relevancy to the question; Sean's cousin Bob gave a Mumble Jumble answer (not Mumbo Jumbo Dr. Bob).
Bob gave a Mumble Jumble answer to Sean's simple question about a fishing trip.
by Deftonio August 21, 2007
Intense mumbling that some people do in a conference-call when they start discussing something at one end, oblivious of the fact that it can't be heard - or understood - by participants at the other end.
My tricky question stumped the unprepared team in the US and they went into a mumble-jumble that made absolutely no sense to us at this end.
by Mohit Hira March 09, 2009