In the absence of air resistance or any other force on it, an object's acceleration is the acceleration of gravity ... <em>9.8 m/s² downward</em>.
It doesn't matter if the object rolled off a table, or fell out of an eagle's mouth, or got shot straight up out of a cannon, or LeBron threw it at the basket for a 3-pointer, or Justin Tucker kicked it for a field goal, or Tiger Woods chipped it for a bogey, or Billy Joe MacAllister heaved it straight down off the Tallahatchie Bridge with all his strength.
It doesn't matter how it got STARTED moving, or how fast it's going right now, or what direction it's going now.
If there's no air resistance, and no OTHER force on the object that can speed it up or slow it down, then it's in "free fall", and it's accelerating at 9.8 m/s² downward.
The size and direction of its MOTION doesn't matter. But the size and direction of its acceleration is 9.8 m/s² straight down.