thimble (n.)youdaoicibaDictYouDict[thimble 词源字典]
Old English þymel "sheath or covering for the thumb," from thuma (see thumb (n.)) + -el (1), used in forming names of instruments (compare handle). Excrescent -b- began mid-15c. (compare humble, nimble). Originally of leather, metal ones came into use 17c. Related: Thimbleful. Thimblerig, con game played with three thimbles and a pea or button, is attested from 1825 by this name, though references to thimble cheats, probably the same swindle, date back to 1716 (see rig (v.)).[thimble etymology, thimble origin, 英语词源]