'Acceleration' doesn't mean 'speeding up'. It means any change in the speed ordirection of motion. Any motion that's not constant speed in a straight line is accelerated motion. Here are a few. I'm sure you can think of lots more.
-- go around a curve on a bicycle or in a car -- jump up in the air and come down again -- jump from a diving board -- stop pedaling or turn off the engine and coast to a stop -- ride a satellite in orbit around the Earth -- stand still on the Earth, and let it spin you around in a circle in 24 hours
