a moon with the penis and balls tucked under so the people witnessing the moon can see your man parts. This makes everything look sort of like a basket of pre-arranged fruit. hence the name... its one of the most unholy things a human being can witness, it makes most gag like the piss snow cone from Jackass: The Movie
The art of showing someone your cock and balls. However this is a specific position where you tuck your cock and balls between your legs and show them to someone from behind. So they look like a banana and two oranges in a bowl, hence the name fruitbasket.
Guy #1:You'll never believe what Derek did at work the other day.
Guy #2:What'd he do?
Guy #1:I went to the storage room to get some supplies and when I opened the door there he was displaying his fruitbasket.