hairspring hairsplitting • hairstone · · · Info · Definitions · Characters · · hairspring · · Text Latin · · Script 10 · · Length Definitions · · · (noun) a fine spiral spring that regulates the movement of the balance wheel in a timepiece. · · Noun Definition 1 Characters · · a latin small letter a U+0061 g latin small letter g U+0067 h latin small letter h U+0068 i latin small letter i U+0069 n latin small letter n U+006E p latin small letter p U+0070 r latin small letter r U+0072 s latin small letter s U+0073