Definition of nut driver in US English:

nut driver

noun

US
  • A tool designed for tightening or loosening nuts, resembling a screwdriver but having a suitably shaped socket rather than a blunt end.

Origin

1930s; earliest use found in Leonard de Vries (b. 1919). From nut + driver, after screwdriver.

Pronunciation

nut driver

/ˈnʌt ˌdrʌɪvə/