'Plethysmograph' definitions:
Definition of 'plethysmograph'
From: WordNet
noun
A measuring instrument for measuring changes in volume of a part or organ or whole body (usually resulting from fluctuations in the amount of blood it contains)
Definition of 'Plethysmograph'
From: GCIDE
- 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}, a. [1913 Webster]