D defs.my
Entry 2 senses Webster, 1913

Tachymeter

· Ta·chym·e·ter · IPA
01 n. An instrument, esp. a transit or theodolite with stadia wires, for determining quickly the distances, bearings, and elevations of distant o…
  1. 1.
    An instrument, esp. a transit or theodolite with stadia wires, for determining quickly the distances, bearings, and elevations of distant objects.(Surveying)
  2. 2.
    A speed indicator; a tachometer.