The Collaborative International Dictionary of English v.0.48:

Kymograph \Ky"mo*graph\, n. [Gr. ? wave + -graph.] (Physiol.)
   An instrument for measuring, and recording graphically, the
   pressure of the blood in any of the blood vessels of a living
   animal; -- called also kymographion.
   [1913 Webster]

WordNet (r) 3.0 (2006):

kymograph
    n 1: scientific instrument consisting of a rotating drum holding
         paper on which a stylus traces a continuous record (as of
         breathing or blood pressure) [syn: kymograph,
         cymograph]