ple·thys·mo·graph (plĕ-thĭzmə-grăf′, plə-)
An instrument that measures variations in the size of an organ or body part on the basis of the amount of blood passing through or present in the part.
[Greek plēthusmos, increase (from plēthūnein, to increase, from plēthūs, quantity, from plēthein, to be full; see pelə-1 in the Appendix of Indo-European roots) + -GRAPH.]
pleth′ys·mogra·phy (plĕth′ĭz-mŏgrə-fē) n.
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