Learner's definition of ROLLER
a part that rolls and is used to move, press, shape, spread, or smooth something
see also steamroller
the rollers of a conveyor belt
They moved the monument on rollers.
He flattened the clay with a roller.
a paint roller
a cylinder or rod on which something (such as a window shade or a map) is rolled up
a small plastic or metal tube around which hair is wrapped to make it curl
a long, powerful ocean wave
a ball that rolls slowly along the ground