Cymatoscope

The term is fairly satisfactory, but has been criticised by the Electrical Times, of London, which paper suggests “cymatoscope” as being more philologically correct, though this paper is not entirely satisfied with its own effort.

Source: wiktionary

The term kumascope, which he had previously himself employed, does not comply with the strict rules of equivalency when Greek words are Anglicized. It is hoped, however, that in this correct form it may meet with acceptance. The word cymatoscope has also been suggested, but although this may be etymologically more correct, the shorter form will no doubt be preferred.

Source: wiktionary

Jenny also used a much more advanced form of wave generation: instead of using a bow string, he was able to create cymatoscopes using piezoelectric generators that could be regulated electronically and could produce steadier wave displacements than any of Jenny’s predecessors.

Source: wiktionary