Definition of plethysmograph in US English:



  • An instrument for recording and measuring variation in the volume of a part of the body, especially as caused by changes in blood pressure.

    • ‘Functional respiratory variables in the animal models were measured with a double-chamber plethysmograph as described.’
    • ‘Lung volumes were measured in a whole-body plethysmograph, and data were expressed as a percent of the predicted values published by Goldman and Becklake.’
    • ‘Lennox and coworkers found that drift of an inductive plethysmography signal was only 22% of the drift arising from changes in temperature within a body plethysmograph.’
    • ‘Thus, the flows estimated in a body plethysmograph may not be fully available to the flow-limited subject.’
    • ‘Hulskamp and coworkers measured lung volume with a new plethysmograph in 32 healthy infants.’


Late 19th century: from Greek plēthusmos ‘enlargement’ (based on plēthus ‘fullness’) + -graph.