"linear measure, one-twelfth of a foot," late O.E. ynce,
(current spelling c.1300), from L. uncia
"a twelfth part," from root of unus
"one;" an early borrowing from L., not found in any other Gmc. language. Transf. and fig. sense of "a very small amount" is attested from c.1350. The verb meaning "move little by little" is first recorded 1599, from the noun. Inchworm
first recorded 1861. For phrase give him an inch ...