A front and back thrusting of the pelvic area whilst grabbing invisible handles in front of your crotch and slowly, but firmly, pulling them closer to your crotch. Rinse and repeat.
Ex: Bob crotch waggled at Taco Bell while ordering an extra girthy Volcano Burrito. Alice filmed it and the cashier, LeSean, took the order and chuckled "hehehe".

Video ex: Go to youtube, search crotch waggle.
by Alex Smith - harbinger of TDs December 18, 2013
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