An incredibly bad(smelling)idea that leaks out of someones head, although these bad ideas can be easily avoided through basic common sense, The term "brain fart" is mostly associated with unavoidable bad ideas that originate from a boss or employer.
Bob's boss looking rather proud leaks out a rather large and foul smelling brain fart by telling Bob "you will have two week work deadlines at the beginning, middle and end of each month".
Bob can easily identify this as a brain fart from the really bad smell and since 2 weeks of time would not exist inbetween the end of one month and the beginning of another.
(can be used as noun,verb or adj. singular or plural)
no sense or value of time, wandering, lost, a waste,a way to start an arguement with the wife
1.) Man that dipshit isn't doing nothing but fiddley-farting around.
2.) Hey that ain't worth a shitload of fiddley-farts.
3.) Alrite bitch, quit fiddely-farting around and fix my dinner !!!!!