from The Century Dictionary.
- noun In machinery, a wheel upon which are radial projections that engage the links of a chain passing over it.
Sorry, no etymologies found.
I tell Polly that Four Oaks is a sprocket-wheel for maids, with two links of an endless chain always on top.
He pointed to a bicycle that was drawn up by the kerb in the approach -- a machine of the road-racer type, with an enormous sprocket-wheel, indicating a gear of, at least, ninety.
That gentleman appears to favour the strenuous life, if one may judge by the size of his sprocket-wheel. "