Haematachometer

Haem`a`ta`chom´e`ter

    (~tå`kǒm´ė`tẽr)
n.1.(Physiol.) A form of apparatus (somewhat different from the hemadrometer) for measuring the velocity of the blood.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.