Thimble, an implement for use in sewing, serving as a protective covering for the finger in pushing the needle through the material worked upon. For ordinary purposes the thimble is a bell-shaped cap reaching to the first joint and is usually worn on the middle finger. It is made of silver or other metal, sometimes of horn, ivory or bone. The sail-maker's thimble or "thummel" is a heavy ring, worn on the thumb, with a disc attached which is the part used to press against the needle. The O.E. thymel, from which the word descends, is formed, with the ,suffix -el, from Hama, the thumb, the protective covering having been formerly worn on that digit. The thumb by etymology means the "thick" finger, and is to be referred to the root tum, to swell up, become thick, seen in Lat. tumere, " tumid," &c. The term "thimble" is used of many mechanical appliances, especially of various forms of sleeve, bushing or joining for the ends of pipes, or shaftings, or as covering for an axle, &c. In nautical usage the "thimble" is a metal ring concave on the outside in which a rope runs; it is a protection against chafing.