My dude, velocity is a vector, if you accelerate a body in a perpendicular direction to its velocity, its velocity will change direction, but not magnitude.
Grab a yoyo, start spinning it around. You are constantly accelerating it towards your hand. If you stopped and let it loose, it would move in a straight line and break the window and mom would be sad.
No acceleration means constant speed in a straight line. If it does not go with constant speed in a straight line, it's being accelerated.
No, the steering wheel does not accelerate laterally. It just changes the direction of the front wheels which dictate the direction in which a vehicle is accelerated.
RCS thrusters for example are accelerators. A steering wheel is not.
Would the steering wheel have the accelerating wheel on the side of the car it is supposed to turn slow down (like how track tanks turn) it would be an accelerator.