a fart that has been hyped up as a big one but disappoints
when someone forces a fart out and it makes a quick but audible noise, usually has the onomateopiec sound ERNT!
an accidental poop halfway through a fart
Peter: Guys I have to fart so bad listen to this!....ERNT!
Dylan: Peter that was a little birdfart
I shouldn't have drank so much last night, when I woke up I birdfarted all the way to the bathroom