Gravity is a physical force which attracts objects toward the centre of the Earth, or any object toward another object of sufficient mass, such as planets toward stars or moons toward planets.
A wizard in Nepal was reported to be growing gravity-resistant trees in the mid-1990s.
Anti Gravity Hats were a joke item sold by Weasleys' Wizard Wheezes. They were hats bewitched to unexpectedly float off of the head of a "gentleman" and "ruin [his] day."
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