The Girth Test is a form of measuring the girth of, or circumference of, a man's penis. When you run out of toilet paper and begin to jerk off, you stick the empty tube on your penis. If the tube fits and your cock slides right in, you have failed. If you can't fit, you passed.
Larry: "Hey man, do you know what the Girth Test is?"
Bob: "No, what is that?"
Larry: *holding empty toilet paper tube* "Let me show you..."
Bob: "What the fuck..?"
by Optiv November 25, 2019
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