̷ ̷ˈ ̷ ̷ ̷ ̷ ̷ ̷+ˌfōn noun
( -s )
Etymology: encephal- + -phone
: an apparatus that emits a continuous hum whose pitch is changed by interference of brain waves transmitted through oscillators from electrodes attached to the scalp and that is used to diagnose abnormal brain functioning