A dolly is a small platform on wheels used to move heavy objects. When furniture movers need to transport a refrigerator or washing machine, they tilt it onto a dolly and roll it instead of trying to carry it. Dollies make it possible to move things that would be too heavy or awkward to lift, using wheels to do most of the work.

In filmmaking, a camera dolly is a wheeled cart that holds a camera, allowing it to glide smoothly across the floor during a shot. This creates those flowing movements you see in movies when the camera seems to float alongside an actor walking down a hallway. The person operating this equipment is called a dolly grip.

The word can also refer to a child's doll, though this meaning is less common today. Your grandmother might recall playing with her favorite dolly as a girl.

In each case, whether it's moving furniture or creating smooth camera shots, a dolly makes difficult work easier by putting wheels under the load.