Long scraggly pubic hair surrounding a man's anus.
You're in the shower at the gym and a guy bends over to wash his ankles, just when you turn towards him.. and you get an unwanted view of his "hairy potter". Usually associated with individuals that have large amounts of back hair, and low personal hygiene.
My friend (who has his pilot's licence) was telling me about his new girlfriend (who was georgous by the way) - and when through detailed description of getting her in the sack for the first time. He complained about how much hair she had down there (likened it to a wookie), and I could help but say - 'your a bush pilot'.