from The Century Dictionary.
- noun The Oriental roller cotton-gin, made of two round pieces of hard wood fixed in a rude frame.
Sorry, no etymologies found.
In India a primitive and cumbersome set of rollers called a churka partially cleaned India cotton.
For the black-seed or sea-island cotton, the churka, or roller gin, used in India from time immemorial, drawing the fiber slowly between a pair of rollers to push out the seeds, did the work imperfectly, but this churka was entirely useless for the green-seed variety, the fiber of which clung closely to the seed and would yield only to human hands.