perview

The act of accidentally seeing a person of the opposite sex partly or fully naked immediately before you enter their space for some legit purpose.

Airline Passenger: Judd, guess what! I got a perview of that hot spanish flight safety attendant because she fogot to slide the bolt to "occupado" while on the john. I was walking in to take a piss and saw her taking a t.p. tour of Forrest Gump, yo!!

Happens all the time to meter readers and letter carriers.