Derived from an ancient "nut-flapping" ritual in Eastern Cambodia. The young boys would yell out "Flapnut!" when the men with the wooden clubs, would "flap" their "nuts" every sunday at 11:38 AM. It has now evolved into an exclamtion of annoying distraction.
When little Billy broke his mother's favorite vase, he threw a fluster of papers and coffe filters into her face and yelled "FLAPNUT!" and escaped before his mother got to him with a the rolling pin.
An exclamation used most commonly with a "?" to signify confusion.
Dude#1: Hey man, I went to a farm and spanked every pig there!
Dude#2: Erp?
Whenever balls, nuts, or testicles are showing and are bouncing or swaying in the wind. See
flapnut
Little Jimmy found it funny to have his balls out in church, little Sally shit her pants in the excitement.
