The Collaborative International Dictionary
Plethysmographic
Plethysmograph \Pleth"ys*mo*graph\, n. [Gr. ? an enlargement + -graph.] (Physiol.) An instrument for determining and registering the variations in the size or volume of a limb, as the arm or leg, and hence the variations in the amount of blood in the limb. [1913 Webster] -- Pleth`ys*mo*graph"ic,
Wiktionary
plethysmographic
a. Relating to plethysmography.