A thimble is a small hard pitted cup worn for protection on the finger that pushes the needle in sewing. Usually, thimbles with a closed top are used by dressmakers but special thimbles with an opening at the end are used by tailors as this allows them to manipulate the cloth more easily. Finger guards differ from tailors' thimbles in that they often have a top but are open on one side.

Some finger guards are little more than a finger shield attached to a ring to maintain the guard in place. The Old English word þȳmel, the ancestor of thimble, is derived from Old English þūma, the ancestor of the English word ‘thumb’.

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