I finally understand where the term "Old Fart" comes from, and I am one.
My sphincter muscles are shot. My ass has fallen [way fallen]. My digestive system apparently has some kind of chemical imbalance that results in lots of gas needing a place to escape. The result is somebody who cannot control her own farts.
The Urban Dictionary has nothing good to say about old farts, but the definition that seems most apt to me is that an old fart is the smell that rises from a couch when you slap it with your hand. [eew!]
It's embarrassing in the library. I'll be up there at circulation checking 'em and checking 'em out. All of a sudden there will be a quiet
e moment (rare in our library) and out will come this little put put sound that is the unmistakable sound of an old fart at work.