The Meaning of "Old Fart"

So, I am visiting my family in New England for the next couple of weeks.

Last night, my sister and I went to my Nana's house for dinner and to spend the night. Nana would NOT stop passing gas (and a LOT of it, if I might add).

She said, "Well now I know why they call us older people old farts! You just don't have control of it any more. . . . What can I say? I'm self-propelled. . ."

TOO FUNNY!