Definition of planometer in English:

planometer

noun

  • A flat plate, typically of cast iron, used in metalwork as a standard gauge for plane surfaces.

    • ‘The latter kind of planometers, although not near so large or costly as the former, has almost an equal range.’
    • ‘Face plates, or planometers, as they are sometimes termed, are supplied by most of the makers of engineering tools.’

Pronunciation:

planometer

/pləˈnɒmɪtə/