Is it farther or further?
1610s, of physical things, from French flexibilité or directly from Late Latin flexibilitatem (nominative flexibilitas), from Latin flexibilis (see flexible). Of immaterial things from 1783.
early 15c., from Middle French flexible or directly from Latin flexibilis "that may be bent, pliant, flexible, yielding;" figuratively "tractable, inconstant," from flexus, past participle of flectere "to bend," of uncertain origin. Related: Flexibly.
flexible flex·i·ble (flěk'sə-bəl)
Capable of being bent or flexed.
Capable of being bent repeatedly without injury or damage.