non-Newtonian liquid is a complex paste or slurry that isn’t quite a solid or a liquid. It can actually exhibit the properties of both a liquid and solid depending on the circumstances. 

Anthony and Tara of Hard Science demonstrate the amazing properties of non-Newtonian liquids with a pool filled with a cornstarch-water mix called oobleck.

With the right speed and pressure, they successfully walk and jump on the slush.