Definition of "antiasteroid"

The juvenile missives from his unmistakably phallic Twitter avatar came days after one of his rockets launched NASA’s first antiasteroid planetary-defense test; a few weeks before another launched a first-of-its-kind mission to study cosmic X-rays; and amid Musk’s sale of 10% of his Tesla stock, a process that roiled markets, cost him billions and should produce enough tax revenue to fund the Commerce Department for a year.

December 13 2021, Molly Ball, Jeffrey Kluger, Alejandro de la Garza, “Elon Musk: Person of the Year 2021”, in Time‎