left test
A rough method of judging a person's rate of aging. To left test is to view a user's current profile picture on Facebook, which is the most recent, and press the left arrow key. This goes back to the user's first picture, when they were younger. It may span several years, or few, and their mileage will vary.
<while friend is stalking someone on Facebook> Damn, give them the left test!
According to the left test, she's like-new.
According to the left test, she's like-new.