interference /-fir″əns/ [L, inter + ferire, to strike] , 1. (in physics) the combination of electromagnetic, light, or sound waves of the same frequency that prevent expected transmission. 2. the erratic transmission of signals from a medical device caused by the simultaneous reception of signals from a source other than that being monitored; for example, the reception of electrical impulses from a nearby IV pump when monitoring the electrical activity of the heart.
