vernier scale

noun

1. Also vernier scale. a small, movable, graduated scale running parallel to the fixed graduated scale of a sextant, theodolite, barometer, etc., and used for measuring a fractional part of one of the divisions of the fixed scale.
2. Machinery. an auxiliary device for giving a piece of apparatus a higher adjustment accuracy.

adjective

3. equipped with a vernier: a vernier barometer.

noun

1. a small movable scale running parallel to the main graduated scale in certain measuring instruments, such as theodolites, used to obtain a fractional reading of one of the divisions on the main scale
2. an auxiliary device for making a fine adjustment to an instrument, usually by means of a fine screw thread
3. (modifier) relating to or fitted with a verniera vernier scale; a vernier barometer

n.

1766, device for making precise measurements, from name of inventor, French mathematician Paul Vernier (1580-1637), who described it in a tract published 1631.

1. A small, movable auxiliary graduated scale attached parallel to a main graduated scale and calibrated to indicate fractional parts of the subdivisions of the larger scale. Vernier scales are used on certain precision instruments to increase accuracy in measurement.

1. French mathematician and maker of scientific instruments, known especially for his invention of an auxiliary scale (named after him) used for obtaining a highly precise reading of a subdivision of an ordinary scale.