Thumb stall
| A kind of thimble or ferrule of iron, or leather, for protecting the thumb in making sails, and in other work. | |
| (Mil.) | A buckskin cushion worn on the thumb, and used to close the vent of a cannon while it is sponged, or loaded. |
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.