[1] : The Collaborative International Dictionary of English v.0.48

tachymeter \tachym"eter\, n. tachy- + -meter.
   1. surveying an instrument, esp. a transit or theodolite
      with stadia wires, for determining quickly the distances,
      bearings, and elevations of distant objects.
      webster 1913 suppl.

   2. a speed indicator; a tachometer.
      webster 1913 suppl.

[2] : WordNet (r) 2.0

tachymeter
     n : a theodolite designed for rapid measurements syn: tacheometer
see also:
tacheometer 

Tachymeter >> T Words
Tachymeter, definition of term: Tachymeter
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