machmeter

from WordNet (r) 3.0 (2006)
machmeter
    n 1: speedometer for measuring the speed of an aircraft relative
         to the speed of sound
    
from The Collaborative International Dictionary of English v.0.48
machmeter \machmeter\ n.
   an instrument for measuring the speed of an aircraft relative
   to the speed of sound.
   [WordNet 1.5]
    

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