plethysmograph
- noun
- /pləˈθɪzməˌgræf/
- Specialized
- During the study, researchers relied on a plethysmograph to assess changes in lung volume.
Examples
-
A respiratory inductance plethysmograph (Respitrace, Ambulatory Monitoring, White Plains, USA) (n20) was used to measure rib-cage and abdominal movements.
Academic text (1991) -
The doctor used a plethysmograph to measure the blood flow in the patient's arm.
-
For accurate readings, the technician calibrated the plethysmograph before the test began.
Compounds
- Specialized
A medical machine with a chamber that surrounds the body to measure lung size and how well you breathe
- Specialized
A small medical device that clips on a finger or toe to measure blood flow
Surface Forms
Morphology
plethysmograph = plethysm + graph
Although the word is structurally built from the classical element 'plethysm' and the suffix '-graph', the first element is not transparent to most English learners, so the meaning is not readily predictable from the parts.
Etymology
The word plethysmograph comes from the Greek parts plethysmo- meaning 'swelling' or 'fullness' and -graph meaning 'to write' or 'record', the same -graph you see in photograph. So a plethysmograph is a device that 'records' changes in how 'full' or 'swollen' a part of the body is, which is why it measures blood or lung volume.