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

tachograph \tach"ograph\, n. gr. ta`chos speed + -graph.
   a recording or registering tachometer; also, its autographic
   record.
   webster 1913 suppl.

[2] : WordNet (r) 2.0

tachograph
     n : a tachometer that produces a graphical record of its
         readings; used to record the speed and duration of trips
         in a motor vehicle

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