Measuring device in the study of pornology. Pornometers are primarily used by pornologists to determine how many P (1 Porn = .666667 inches) are in any given pornograph. The pornometer is a long device that is firmly attached to the scrote. Special care should be taken to calibrate it.
"Whoa I just received a pornogram from PetCo."
'Let me whip out my pornometer and appraise that for you'
"No, put that away; there are children here."