Padadger
A padadger is when your boner just randomly decides to come out and play, even when it's not needed. It's like your junk is a kid with no respect.
I got a padadger during my lunch break. I had to eat in the bathroom.
My friend got a padadger in the grocery store. He almost dropped his bag of chips.
I got a padadger while I was walking. I looked like a fool.