electrocardiograph
From Longman Dictionary of Contemporary Englishelectrocardiographe‧lec‧tro‧car‧di‧o‧graph /ɪˌlektrəʊˈkɑːdiəɡrɑːf $ -troʊˈkɑːrdiəɡræf/ noun [countable] technical x-refan ECG(1)Examples from the Corpuselectrocardiograph• During the entire study the subjects electrocardiograph was displayed on a monitor.