— plethysmographic /pleuh thiz'meuh graf"ik/ , adj. — plethysmography /pleth'iz mog"reuh fee/ , n.
/pleuh thiz"meuh graf', -grahf'/ , n.
a device for measuring and recording changes in the volume of the body or of a body part or organ.
[ 1870-75; plethysm ( ós ) increase, multiplication ( plethý ( nein ) to increase, deriv. of plêthos large number, crowd + -smos, var. of -mos n. suffix) + -O- + -GRAPH; first coined in It as pletismografo ]