The Collaborative International Dictionary of English v.0.48:

Hemadynamometer \He`ma*dy"na*mom"e*ter\, n. [Hema- +
   dynamometr.] (Physiol.)
   An instrument by which the pressure of the blood in the
   arteries, or veins, is measured by the height to which it
   will raise a column of mercury; -- called also a
   h[ae]momanometer.
   [1913 Webster]