electrokymograph (n.)

An instrument used in ARTICULATORY PHONETICS to enable a record to be made of the changes in ORAL and NASAL airflow during speech. Electrokymography involves the use of a face-mask which can differentiate the two kinds of flow, and associated equipment which can measure air volume and velocity, and record it visually (as an electrokymogram). It is a development of the earlier kymograph.